


Kinktober 2017 - Alphyne Edition

by Omoni



Series: Undertale Writing Challenges [3]
Category: Undertale (Video Game)
Genre: Alphynecentric, Alphys/Undyne-centric, Body Swap, Cunnilingus, Dirty Talk, Established Alphys/Undyne, F/F, F/M, Face-Sitting, Foursome, Gay Sex, Hand Jobs, Kink, Kinktober 2017, Knifeplay, Lapdance, Laughter, Lewff, Lingerie, Masturbation, Mirror Sex, Nerds in Love, Orgasm Delay/Denial, Overstimulation, Romance, Scars, Sensory Deprivation, Sex in questionable places, Shower Sex, Sixty-nine, Sleepy Sex, Smut, Stripping/Striptease, The last chapter is such a big surprise that even I don't know what it is, Tickling, Wall Sex, Waxplay, cross-dressing, sappy romance, sex with feelings, sexy body swap, spouse swap, those tags make me laugh, yes that's a real thing
Language: English
Status: Completed
Published: 2017-10-01
Updated: 2017-11-03
Packaged: 2019-01-07 19:56:01
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 30
Words: 43,864
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/12239610
Author URL: https://archiveofourown.org/users/Omoni/pseuds/Omoni
Summary: My collection of fics for Kinktober 2017! Each chapter will be based on one of the three offered prompts for the month, one for each day of October! This is incredibly NSFW, so be warned, and it's obviously full of sex, lewff, and smut. Enjoy!





	1. Sleepy Sex

Undyne woke up slowly to the most wonderful feeling: Alphys cuddling against her and kissing her neck. Her moves were slow and lazy, betraying her own lethargy, but Undyne didn't mind. Instead, she smiled widely, keeping her eye closed, and slipped her arms around Alphys, pulling her closer. Alphys slid herself atop of her and wrapped around her like the best of blankets, her lips still trailing kisses up and down her neck, and soon Undyne was purring softly, her nails digging into the small of her back.

Alphys shifted down lower, her lips making a path down from Undyne's neck to her breasts, still kissing in that soft, fluttering way that had Undyne feeling warmer and warmer the longer she went on. She had no idea what time it was; just that it wasn't even dawn, but she didn't care. When she felt Alphys trail the tip of her tongue along one of her nipples, she gasped softly, squirming beneath her and shifting her hips up against Alphys's.

Alphys paused, making a sound of her own from that, her eyes closing and her own hips moving down to meet that thrust, and in reply to it, she moved one of her hands down between them and trailed her fingertips lightly over Undyne's folds, feeling a spike of heat hit her when she felt how slick she already was. Undyne growled from deep in her throat, her hips once more moving up, and Alphys shifted, pulling away from her breasts to catch her breath, her own body alight with desire.

Undyne then grabbed her wrist and pulled it away from between her legs, surprising her into looking up. Undyne looked back at her, her eye half-open and dark with need, and Alphys moved back up to kiss her lips hungrily, pressing her body down against her, making her purr again and hold onto her so tight that her nails bit into her skin.

Undyne then moved her legs, trapping Alphys between them, and as their kiss deepened, Alphys reached between them again, only this time, she used her hand to make sure that their flesh touched, their clits meeting as close as possible. Undyne's eye shut and she groaned against Alphys's lips, something that had Alphys murmuring in return, before she moved down and rubbed close.

Again, Undyne groaned, grabbing Alphys's other wrist and pulling it to her side, so that her fingers touched her gills, and Alphys smiled against her lips, trailing the tips along the sensitive grooves in such a way that Undyne practically melted beneath her, her hand returning to Alphys's back to dig in hard. Alphys moved her other hand to Undyne's other side and did the same, and Undyne pulled from their kiss to tilt her head back and gasp, her whole body flooding with peals of sensitive pleasure.

Alphys licked her lips, her own arousal increasing at the sight of Undyne's, but she kept her moves achingly slow, even when Undyne tried to speed things up. It was the sweetest kind of pleasure, one that crept up on them both slowly, though for Undyne, of course, it was quicker - and far more intense - the longer Alphys stroked her gills.

Undyne felt her orgasm crest through her slowly, so slowly it was like a trance, one made purely of this, this physical bliss that she knew only Alphys could give her. With a desperate cry, her lips sought Alphys's, finding them eagerly awaiting hers, and they kissed, even as Undyne cried out and lost control, her body stiffening and shaking beneath Alphys as she came. Alphys kept her moves slow, drawing it out as best as she could, and Undyne was lost, utterly lost, to her - and loved every moment of it.

When she calmed, she opened her eye and looked up at Alphys, whose eyes fluttered open and met hers, still dark with unsatisfied lust. Undyne reached down and pulled her hands from her sides, instead holding them in her own, and Alphys pinned them to the bed, her eyes closing again as Undyne shifted her hips upwards once more, sending a sharp stab of pleasure into them both. Alphys buried her face into Undyne's neck, her breaths catching and going hoarse the longer they moved, and Undyne smiled, her own eye closed.

Alphys then moaned out Undyne's name, her hands holding Undyne's so hard she felt her claws bite into her skin, but she didn't pull away. Instead, she hooked her legs around Alphys's hips tighter, pulling her down closer, and Alphys cried out again, the sound so full of need that Undyne felt it deep in her own heart. Alphys staggered against her, arching back and keening out as she finally peaked, and Undyne held her close, her own heart racing with love and happiness.

When she was spent, Alphys collapsed atop her, gasping for breath, her hold on Undyne's hands loose, now. Undyne nuzzled her cheek, and she smiled, kissing Undyne's cheek in return, and for a moment, they kissed, feeling the thrums of pleasure slowly fade from their bodies - but not from their hearts.

Then, Alphys curled up close, wrapping herself around Undyne again, only this time, her body was heavy with fatigue. Undyne pulled her as close as possible, her own body relaxing, and they soon were pulled back into sleep, their thoughts - and dreams - only of each other.


	2. Dirty Talk

It was probably the silliest thing she'd even done, but Undyne couldn't resist.

She and Alphys were watching a movie, and both were actually finding it rather disappointing. But they'd paid a lot of money to see it, so both were kind of holding out, hoping it would eventually get better.

It did not.

So Undyne, noticing that Alphys was frustrated - she was glaring at the screen in front of them, her arms crossed over her chest and her tail twitching angrily - decided to distract her.

She leant close, grinning, and whispered, "Hey, Alphy."

Alphys nodded, still glowering at the screen.

"I think, when we get home, I wanna try some things with you," Undyne continued, moving so that she could not only lean as close as possible, but put an arm around her. Alphys leaned into her embrace and nodded again, and Undyne went on.

"I think, when we get home, I'd like to absolutely jump you," she whispered. Alphys's eyes widened, but Undyne was nowhere near done. "I want to get you home, pin you against the wall, and take your clothes off slowly, a piece at a time, and I want to make sure every single inch of skin you show will be covered in my kisses."

Alphys blushed, shifting a little in her seat, and she bit her lip, her eyes finally going to Undyne's. To her delight, Alphys nodded again, and Undyne immediately was hers.

"Every single stitch of cloth, I want off of you, and on the floor," she murmured, her hand moving up to touch her cheek. "I want you to be naked, wanting me - _begging_ me - and I want to keep you hanging, keep you begging, and I know just how I'd do that, too."

"Undyne..." Alphys whispered suddenly, her eyes flicking around them to make sure no one could hear them. They were at the very back of the theatre, so there was no chance of that, but she checked, anyway.

"You wanna know how?" Undyne asked, and Alphys shivered, nodding and leaning closer. "I'd start with kisses, sure, but then I'd start licking: your lips, your neck, your shoulders... but then I'd go right to your breasts, making sure you can't touch me back, pinning your hands to that wall as I'd lick your nipples into that hardness I can't get enough of."

Alphys exhaled shakily, her eyes closing and her arms uncrossing, and one hand went right to Undyne's knee, her claws digging in.

"And then I'd start biting," Undyne admitted, her hand trailing along the curve of Alphys's neck. "Gently at first, but harder the lower I'd go, leaving marks all over your beautiful body, just to show I was there and that I'm yours - and you're mine. And then, while you're still begging, I'd grab you by the hips, pull you up, and dive right in, licking slowly along your slit as you grab my hair and tug. I'd get so drunk on that taste that I'd never stop, even if you come once, twice, however many times it takes, for you to scream out my name and beg me to fuck you."

Alphys was shaking, now, her eyes closed and her other hand holding onto the armrest of the chair, so hard her claws dug into the fabric and left holes.

"But I wouldn't - not yet," Undyne admitted, her voice wavering a little in her growing arousal. "I would tease you, start biting again, and bury my hand deep within you, making sure to stroke your insides with my fingers, making sure I touched that spot that makes you squirm and keen and dig your claws into my skin. I'd kiss the pleas from your lips, swallowing them like the best of wines, and I'd get even drunker on you, while you get drunk on me, too."

 _"Undyne..."_ Alphys repeated, her voice tiny and shaky. Already, Undyne could hear those pleas, and she shivered, slipping her hand beneath Alphys's shirt to trail her fingers along her shoulder and collarbone. She felt Alphys's skin break out into gooseflesh, and she leaned even closer, not able to quit, now.

"And then, _only_ then, when you're a mess and every word that comes from you is my name," Undyne replied. "Then I'd bring you to our bedroom, lie you down, and finally get naked, myself - but I wouldn't let you touch me, not until I have you in my arms and are fucking you so senseless that we _both_ go crazy from it."

"Oh my _god..."_ Alphys murmured, especially when Undyne's hand trailed low enough to trail her fingertips over her breast - and her hardened nipple, the feel of which thrilled Undyne.

"And we wouldn't stop, Alphy," she said, her voice still a whisper. "Not until the sun comes up, and not until we both pass out." She leaned closer, kissing Alphys's cheek lightly. "How does that sound, my love?"

Alphys turned to her, her eyes dark and her face scarlet, and she gasped out, "Take me home. Take me home, _now_. Now, Undyne, _now!"_

Undyne grinned, got to her feet, and picked her up - a good thing, that, as Alphys was positive she had no knees - and they practically ran home, the movie forgotten completely.

But once they got home, nothing was forgotten. Not for the rest of their lives


	3. Public

**Notes for the Chapter:**

> I know, it's a day late! Shh!

Alphys realised later that she was probably the most inappropriate, overtly horny, and lust-filled monster in the entire world, but in the moment, she didn't even think those things. All she could think about was her wife - and how damned sexy she could be without even trying.

It started innocently enough, truly: a day off together on the weekend, one they decided to spend eating out and shopping for things they needed, but never had time to get during the week. This included clothes.

Both Alphys and Undyne hated shopping for clothes in public. Undyne usually shopped online, while Alphys settled for her favourite clothes or rare treasures found in the dump.

But it needed to be done, as both needed dressier clothing to go along with being teachers, so they both resigned themselves and went.

Lunch went well, at least, as the food court - especially a human one - was always a favourite for them both. But once they were done and they headed to the clothing stores, they both felt a little grumpy.

This, however, didn't last, and it was entirely Alphys's fault.

Undyne, it should be known, actually liked skirts and dresses. She kept it a secret - "If anyone found out that I like looking like a cupcake sometimes, they'll never take me seriously!!" - but Alphys knew.

She also didn't like wearing them on the surface too often, as humans had weird stigma about body hair and Undyne refused to shave her legs. But she also didn't like calling attention to herself that way, so she still kept that secret close to herself.

But today, Undyne decided she was done trying. A heatwave had hit the surface, and the heat was unbearable for Alphys, let alone Undyne.

So, after lunch, she'd glared at Alphys and snarled, "I'm buying shorts and skirts and short skirts today, and if the humans don't like it, I'll feed them spear."

Alphys stared at her, feeling blood rush to her cheeks at the sudden mental images. Undyne had excellent legs, and to Alphys, the more she showed them, the better.

"I'm not fucking shaving, Alphy!" Undyne added fiercely, her voice loud enough to carry around them and into the ears of nearby humans, who turned to her with mixed expressions.

Alphys, however, nodded and smiled at her. "Yes, please!" she agreed. On a whim, she brought one of her feet from under the table to Undyne's leg, reaching with her toes to touch her shin right under her pants. Undyne grinned at that, blushing in return, but her eye shone, and Alphys was happy.

They chose a store suited for Undyne, first: tall and lanky. Alphys eyed a few sweaters (and ended up buying two), but Undyne was immediately pulled to the rack of skirts, and she grabbed at least six before a clerk even saw her. When Alphys caught a glance at the expression on the clerk's face, she laughed: the clerk was clearly bemused, as Undyne had swooped down on the rack like a hawk on a shrew.

"Alphy!" she called over her shoulder. "I need your help, c'mon!"

Alphys blinked, blushing, and glanced at the clerk, who rolled their eyes but nodded, and Alphys vanished to the changerooms with Undyne.

It was a mistake.

Well, for the clerk, anyway.

Alphys sat on the bench as Undyne changed into the first skirt, watching her easily enough - to start. When Undyne smoothed that first skirt over her legs and revealed that it only came up mid-calf, Alphys found herself suddenly very interested.

"Hm," Undyne murmured, eyeing herself closely in the mirrors. "Not bad, right? I like the colour."

Alphys nodded, blushing a little. "It's very nice," she agreed, her hands holding her knees rather tightly.

Undyne raised an eyebrow at her through the mirror, and she blushed deeper, but didn't look away. "Alright, cool," Undyne agreed, pulling the skirt off and setting it aside. She grabbed another one and pulled it on, and this time, Alphys squeaked.

It was shorter than the first, reaching just above Undyne's knees, and in soft pleats that added volume to her modest hips, but showed off her legs excellently. Alphys stared at those legs for a moment, then gultily looked up at Undyne - who was watching her with a grin and her hands on her hips.

"Oh ho," Undyne murmured, her grin widening. "I think someone likes skirts, too."

"J-just on you," Alphys admitted, her claws digging harder into her knees. "Y-you look v-very..." She swallowed, her throat dry. "Oh, god, Undyne, I'm sorry, but you look _so_ sexy."

Undyne's eye widened, and a hand went to her cheek, turning back to the mirror with a blush of her own - and a slight shift in her posture. "Sexy?" she echoed. "C'mon, Alphy, it's just a skirt!"

"That _you're_ wearing," Alphys added.

Undyne touched the sides of the skirt shyly, then blushed deeper and tried to look away, only to be thwarted by the myriad mirrors around her. "Ehhh," she muttered, conflicted; she wanted to be sexy, sure, but only for Alphys - and the fact that she had achieved her goal made her think very inappropriate things, indeed.

It was the same for Alphys. She bit her lip, staring up at Undyne with wide eyes, and Undyne stared back, noticing a similar hunger, there, that she felt, herself.

"Fuck," Undyne growled, darting over to her and sitting in her lap, just as Alphys raised her hands and grabbed hold of her to pull her close. They kissed, Undyne pressing down and close against Alphys, and Alphys clung to her, her hands reaching up under that skirt and moving over her hips, her rear, and her thighs, then back up again.

"Shh," Alphys murmured against Undyne's lips between kisses, and Undyne nodded, her eye closed tight and her body shifting against Alphys's caressing. Alphys hooked a claw around the waistband of Undyne's underwear, tugging them down, and Undyne nodded again, pulling away and grabbing the front of Alphys's pants, fingers scrabbling to pull them off and down.

For a moment, they moved apart, their eyes flicking to the door to make sure it was locked, before they both wiggled out of aforementioned unnecessary clothing.

However, when Undyne moved to pull off her skirt, Alphys quickly stopped her, her face bright red. "N-no," she whispered. "Keep it on."

Undyne grinned, then nodded, hiking it up a bit in order to sit on Alphys's lap properly. She adjusted it to fall over them both in a nice way, and after a moment of further adjustment, their legs were entwined and they were at it, right on that bench and in the changeroom.

It was a bit of a struggle; Undyne was eager, turned on by Alphys's own arousal, and Alphys was even more eager, her claws digging into Undyne's backside rather hard, but neither even considered stopping. They were as quiet as possible, only the occasional squeak or muffled cry escaping them, and only once did the clerk come by.

"You alright in there?" they called, scaring them both into freezing in place - just for a second.

"Yup!" Undyne replied, her voice oddly calm. Alphys stared at her in amazement, especially since she hadn't stopped grinding against her. "Just need a bit more time to try these on!"

She reached down and covered Alphys's mouth, just as Alphys eyes shut and her claws bit into Undyne's skin. When the clerk hesitated, Alphys held her breath, already so close and yet unable to let go, knowing the clerk was right there...

"Alright," the clerk finally concluded. "Let me know if a size doesn't fit right."

"Will do!" Undyne chirped, her eye glinting mischievously as she leaned down and replaced her hand with her lips, covering Alphys's mouth in a far better way.

"How the hell did you manage _that?!"_ Alphys demanded breathlessly.

"Skills," Undyne grinned back. "Come for me, please."

Alphys blushed even redder at that, especially since she said it so confidently and easily. But, truly, she was close, and she buried her face into Undyne's chest, pushing her hips up against Undyne's each time she moved against her. Undyne hissed out, her eye closing tight, leaning down and kissing Alphys's neck close, and when Alphys gasped, she reached up and covered her mouth again quickly.

But then, Alphys grew clumsy, and she grunted, her eyes squeezing shut tight. She struggled to stay quiet, but knew she was failing, and she reached up, herself, and covered Undyne's hand with her own, muffling her sounds just in time. She came, her eyes rolling up, and Undyne bit on her neck, growling in return, the sight of Alphys coming breaking her own hold shortly after. They stumbled a little, almost falling to the floor, but Undyne clung to Alphys tight, keeping her close. 

They breathed hard, leaning against the wall behind them to catch those breaths, and finally, both Alphys and Undyne dropped their hands from Alphys's mouth, relaxing against each other in shared bliss.

After a moment, Undyne whispered, her grin all teeth, "So.... should I buy this skirt?"

Alphys laughed and nodded, pulling her close into a tight hug.

(When they left to pay for the skirts and sweaters, the clerk was glaring at them. They both blushed, but also smiled, and realised as one that they were likely banned from that store for life. It was worth it.)


	4. Begging

It was torture. Absolute torture.

But at the same time, Undyne was rather happy, all things considered. She was making out with Alphys, it was true, and Alphys knew how to make out - she was excellent when it came to using of her tongue and fingers - but she was also a master at holding off and making Undyne _crazy_.

Case in point: they were making out on the couch, Alphys having crawled into Undyne's lap in the middle of a game and started kissing her like there was no tomorrow, her hands cupping Undyne's breasts in such a way that had her leaning back and gasping for breath, squirming as heat filled her.

But every time Undyne moved to take a piece of clothing off of Alphys, she jerked away and pulled Undyne's hands off of her. When Undyne looked up at her, she merely grinned, instead focusing on Undyne's clothes - something Undyne followed through with easily.

Alphys took full advantage of this, leaning down and licking along Undyne's neck, her shoulder, her collarbones, until finally her lips landed on one breast, then the other, causing Undyne to cling to her and shiver.

"Alphy," she growled out, "Touch my gills?"

Alphys smirked, but shook her head, and Undyne stared up at her, bemused and practically starving for that touch. _"Alphy!"_ she cried, trying to grab one of her hands to her side.

But again, Alphys pulled her hand away, instead using it to stroke her breast and nipple slowly. Undyne was starting to lose control, her breaths hoarse and her body blazing, and when she tugged desperately at Alphys's shirt, Alphys pinned her hands to the back of her couch, instead.

 _"Augh!"_ Undyne blurted out, arching back and grinding her hips against her wife's. "You're _killing_ me! For _fuck's sake,_ Alphy, please, please, _please!!"_

By the time she got the last word out, Alphys's hand was suddenly there, right at her gills, and Undyne burst out a laugh, relieved. She clung to Alphys as she stroked her gills, her body moving with each touch.

"I like that," Alphys suddenly whispered into her ear, licking it a little.

"Like _what?"_ Undyne growled out, her eye shut tight.

"When you plead," Alphys concluded. "It's _hot."_

Undyne stared at her again, her eyebrows raised, but Alphys grinned back, her eyes gleaming with arousal.

It was a challenge, and Undyne grinned back. "Oh? You like it when _I_ beg? I seem to remember, one night, _you_ unable to do anything _but_ beg."

Alphys raised an eyebrow, then brought her other hand to Undyne's other side, and started stroking her gills there, too. Undyne's eye darkened and closed, and she buried her face back into Alphys's neck, her bites a little sharper. She arched her hips up again, something Alphys retaliated with a shift of her own, and soon, Undyne was growling again, her hands clutching at Alphys's shirt and pulling desperately.

Alphys grinned wider, leaning back down and licking one of Undyne's nipples in reply, and Undyne grunted, the sound holding a slight edge to it.

Then, in a soft voice, Undyne murmured, "Please, Alphy? Please, get naked?"

Alphys pulled away immediately, sparing little time in getting topless, and the moment she was, Undyne grabbed her back, burying her face between her breasts and sighing deeply, her fingers digging into her back. Alphys resumed stroking her gills, and Undyne cried out, the sound muffled but still loud enough to send shivers up Alphys's spine.

"More," Undyne whispered when she could. "Oh god, Alphy, more, _more!"_

"More, what?" Alphys wondered, whispering it into her ear.

"More fucking, please!" Undyne cried, unable to hold back her urgency. Her hands were now at Alphys's hips, trying to tug her pants off, and Alphys laughed softly, a sound that only made Undyne feel even more desperate.

But then Alphys pulled away and stood up, pulling her pants down and off, and Undyne quickly followed before Alphys could stop her. That was fine, as the moment Alphys was back atop her, she was teasing her, again, and Undyne was about to lose her mind.

 _"Augh!"_ she shouted, burying her face into Alphys's shoulder, her hands holding Alphys's wrists and pulling them from her gills. "It's _not_ enough, stop torturing me! _Please,_ for the love of _fuck,_ Alphy!"

Alphys grinned, then nodded, shifting so that she was straddling Undyne properly - at last. The moment their flesh met, Undyne moaned, clinging onto Alphys tight and urging her to move fast - and hard.

This was no problem for Alphys, as she was quite fired up, herself, and in no time, Undyne was peaking beneath her, uttering Alphys's name in a hoarse plea that had Alphys shivering with delight. Undyne had barely enough time to recover before Alphys was tumbling after her - almost literally, as Undyne had to grab her before she fell off the couch.

Then, for another moment, one far longer, they remained a shared puddle on the couch, gasping for breath and grinning.

When she could, Undyne murmured, "I'm gonna get you back for that."

Alphys laughed tiredly, but inside, she felt a thrill. "I look forward to it."


	5. Body Swap

**Notes for the Chapter:**

> This was way too much fun to write, so I broke it into two chapters between two prompts. The next part is the next prompt, so if you want the rest, be patient! :D

They didn't know how it happened - to start, anyhow - but once it did, and once they got over the shock, they spent the entire day purposefully testing it out - especially on each other.

They'd had a rather intense session of sex the night previous, and both woke in that sleepy, satisfied way that comes with sex like that.

It was the first hint of how it happened.

But that sleepiness and lazy grins lasted mere seconds, and for good reason, too. When their eyes met, they both froze, mouths opening in shared shock.

"Alphy," Undyne said, her voice shaking.

"Undyne?!" Alphys agreed, her own voice cracking.

Because the voices they spoke with were not their own, but each other's.

"Ah!" Alphys cried, her eye wide and her hands going to her face - a face familiar, yes, but not like this. "Ah! Ah! _Ah!!"_

Undyne's eyes were huge, and she reached up and touched her own nose - and made a surprised sound of pure disbelief.

"I'm--!" Alphys cried.

"-- _you!"_ Undyne cried in return.

"What the _fuck?!"_ Undyne added, finding it very strange to hear that phrase in her wife's voice.

It was a sentiment Alphys could agree with, as she was having quite a time adjusting to this. Undyne's body was very tall, very lanky, and practically bursting with energy, surprising for so early a morning. However, Alphys was unused to only having one eye, and it was strange to have the left side of her vision blocked. She reached up and touched Undyne's - her - hair, and blinked.

Undyne, however, it must be said, was a touch more inappropriate. She was amazed to find that, although her body was a little slower than what she was used to, Alphys was still rather full of energy, herself. She blinked, then grinned, reaching out and wagging her tail, and she laughed, swinging it back and forth a little, before her thoughts went downhill.

She immediately reached down and touched her breasts, grinning when she remembered that Alphys and herself had gone to bed naked. Touching these very same breasts in such a different way was very, very interesting, indeed. She didn't have big breasts, herself, so to touch them - and feel them as part of her body - was fascinating.

"H-hey!" she heard her own voice stammer, and she opened her eyes and looked up, feeling a strange uncanniness at seeing herself look so shy and indignant. "Wh-what--? _Stop that!"_ Alphys added.

Undyne blinked, only now noticing that her vision, though complete, was rather fuzzy and blurry. Despite that, when close enough, she could see Alphys just fine, and she smiled, still groping her own - borrowed - breasts quite happily, especially when it started to feel good.

"Can't help it," Undyne replied. "You're still hot."

Alphys stared at her, then grinned. She felt that grin spread wide on her face, and idly, she ran the tip of her - far shorter - tongue along those sharp teeth. She felt a little shiver at that, and slid her hands through her hair slowly. The feeling was nothing that Alphys had ever experienced before, and she realised that it was no small wonder Undyne loved her hair to be loose and played with.

"O-oh," she murmured, her eye fluttering closed. "Th-this is n-nice..."

Undyne blushed, then had an idea. She reached forward - stared at her hand for a moment - then took hold of one of Alphys's - her own? - and pulled it away from her hair. Alphys opened her eye, smiling faintly, and Undyne jolted, surprised; seeing that look of affection upon her own face, when she was so used to seeing it on Alphys's, was startling. She had no idea her own face could even look that way.

But then, she shook it off, and pulled that hand down to her side, and placed it right over her gills. Alphys's eye flared in surprise, but Undyne grinned wider (and in turn, she had Alphys marvelling at that expression, as it was one she never knew she could make, either) and cupped her hand over them.

Something sparked in Alphys's eye at that, her breath sharply catching the moment her fingers touches those grooves.

"Touch 'em," Undyne urged. "When are you gonna get another chance like this? You'll finally get why it makes me crazy!"

"O-oh," was Alphys's reply, whether as an answer or a reaction, though, was not certain, as she just started to trail her fingertips over them slowly. Shivers of pleasure slipped through her skin, and she shuddered, hiding her face in the closest pillow and squirming, but not stopping. It was an intense kind of pleasure, similar to that of overstimulating her clit, but sharper, and different.

On _that_ thought...

Alphys's other hand suddenly went between her legs, her fingertips trailing over soft hair, and she sighed, once more amazed by how good that felt. _Hair is amazing,_ she concluded. _I wish I had hair._

"Hey..." Undyne murmured, though she sounded more amused than anything else. "Whatcha doing, Alphy?"

"Experimenting," she murmured, her voice muffled.

Undyne shifted closer, intrigued, and again, she slowly ran her palms over her own breasts, looking down and enjoying the sight of her body that wasn't really hers.

"Dunno when this'll wear off," Alphys went on, squirming again, especially when she slipped her hand between her legs. "Wanna make use of... _oh_...!" She shifted, rolling onto her back, both hands busy, now. "That's... th-that's _wonderful_...!"

Undyne felt herself blush, only not just her cheeks, but her whole body. The gesture was accompanied by a wave of sharp heat, and suddenly, she realised precisely why Alphys got so wild when she was horny: her body was practically made for it.

"Hey," she murmured, hearing herself speak in that tone that usually got her hot and bothered when on the receiving end of it. "Wanna feel how I feel when you touch me?"

"Mm!" Alphys agreed, her eye still shut tight and her hands still rather busy.

"Alphy...!" Undyne laughed, blushing a little at that. Clearly, Alphys was just fine where she was, and found Undyne attractive no matter the contest.

Honestly, Undyne could relate. Finding herself in her wife's body was very, very interesting, and the longer she spent within it, the less control she was having over her own feelings.

So, with familiar-yet-not fingers, Undyne reached forward and touched Alphys, trailing her fingertips lightly over the gills on her other side. Alphys jerked in surprise, her eye opening and going right to Undyne's.

"Whoa!" she cried, scrambling a little to move closer. "Th-that--! That's _my_ hand?!"

Undyne laughed again, finding it funny to hear it in Alphys's voice, but she didn't stop her hand. Instead, she murmured, "Now touch me. I wanna know how it feels for you."

Alphys nodded, starting to get used to this weird feeling of being so long and strong. With slightly shaky fingers (Undyne was still touching her, after all), she brought her hand towards Undyne (really, her own body, seeing herself this way was so strange!). With a little jolt, she thought of what Undyne's hands upon her body could do, and she trailed her hand along her - no, Undyne's - side. She had no gills, but when Undyne did that, she always felt heat fill her.

Sure enough, Undyne felt it, shivering a little and closing her eyes halfway. "Huh," she murmured, though her voice wavered. "That's... fucking _awesome_... I can really touch you that way?! That's all it takes?!"

"Er!" Alphys answered, suddenly wishing her had a tail to hide behind. Instead, she shook her hair in front of her face, obscuring both her features as well as her vision, and was satisfied.

Undyne laughed again, still finding Alphys adorable, even if she wasn't in her own body. She shifted closer, wrapping her arms around her waist, finding it oddly fun; she could really feel the size difference between them this way, and it was neat.

Almost. "Hm," she murmured, "I'm not very soft, am I?"

Alphys immediately pushed her hair away, her face a scowl. "What?! Yes you are!" she growled, moving up closer to prove it. When she did, she blinked, and suddenly understood what Undyne meant: her body _was_ rather soft, wasn't it?

"Wait," she added, confused by her own thinking. "I-I don't feel that way! I'm too heavy and fat to feel that way!"

"Guess again, nerd," Undyne answered, slipping her tail around and hooking it around Alphys's thigh, like Alphys always did for her. "Though I have to admit, I'm really glad I work out. You do feel nice and strong against me."

"Mm! Yes, exactly!" Alphys agreed, giggling a little when she felt that tail. "And you hug in the best way!" And she turned around and grabbed Undyne into an embrace to prove it.

Then, they both paused, the feeling both familiar and alien to them both, and they wanted to experience it fully.

"Alphy," Alphys heard her own voice whisper.

"Yes?" she murmured back.

"You're right. Let's not waste this. C'mere."

They spent the entire day in bed. The effects - eventually concluded to be the result of too much souls sex - wore off close to the evening, but that didn't mean they didn't make the most of it.

Far from it, in fact.


	6. Size Difference

It was a truly bizarre experience, to have sex with yourself. But both Undyne and Alphys were more than up for it. And Alphys made sure to make mental notes for later, so that she could write this all up; there was no way she wouldn't, not when it came to soul magic.

They started slow, to be honest, as they both were still adjusting to this new reality. But soon, Undyne was starting to feel not only Alphys's body's arousal, but her own, and she couldn't keep her hands to herself - so to speak. It was even worse, because she already knew her own body's weaknesses, and it didn't take very long to have Alphys writhing on the bed beneath her, begging her in Undyne's own voice for more, more, _more_.

She started with her hands, truly finding it fascinating to feel her own body this way. She was so used to it that seeing it - and feeling it - this way made her appreciate it more. She was slender, but solid, and her body's lines and curves were modest, but still well-defined. She personally didn't find herself as sexy as Alphys clearly found her (she kept starting to masturbate if Undyne took too long to touch her, which made her laugh every time), but if she closed her eyes, she found it easier.

Alphys was a puddle. Being in Undyne's body was amazing and arousing all on its own, but since Undyne knew all of the right places to touch, she was immediately at her mercy and loving it. It was weird to see Undyne in her body and touching her, but like Undyne, if she closed her eye, she could easily disconnect and enjoy it all.

When Undyne touched her and slid her fingers up and along her folds, Alphys was amazed by how well she did it; every touch was intentional, and brought sweet peals of pleasure through her whole body. When Undyne placed her fingers around her clit, so that it was right in the middle of them, and started rubbing slowly, the feeling was absolutely perfect.

"Oh my god," Alphys whispered, her voice hoarse. She was clinging to Undyne, feeling her own body against her as she did, and Undyne chuckled softly, leaning down to kiss - then bite - the curve of her neck hard. Alphys cried out, her whole body going hot, and a small part of her made notes, making sure to remember all of this to apply later, once things were normal again.

Undyne was soft against her, and holding her was strangely comforting. Her body loved the feel of Undyne against her, and Undyne was making sure that she would, too. She wanted Alphys to know how much she adored Alphys, as Alphys, herself, never really believed it.

Now she was starting to believe it. Holding Undyne, burying her face into her shoulder and kissing her there, shifting her body along hers... She felt amazing, and in turn felt amazed by that fact.

Undyne kept the pace of her hand slow, her heart racing fast within her breast, her grin almost feral and her eyes blazing. Alphys made a soft sound, her hips moving up and against Undyne's. "God, that feels _so good,_ Undyne..." she murmured breathlessly. "I'm... I feel really close already..."

"Mm," Undyne replied, slipping her head down and trailing the tip of her tongue along her nipple closely. It instantly hardened beneath it, and she grinned even more, suddenly curious.

"Hey, Alphy," she murmured, "wanna know just how great your tongue is?"

 _"Fuck,_ yes, _please,"_ Alphys gasped out, nodding so hard that her hair fell into her face. "I sw-swear, you're next, but pl-please, _please_ , y- _yes!"_

Undyne pulled away and pushed her down onto the bed, then knelt in front of her and pushed her legs apart, bringing her legs up onto her shoulders and digging her claws into her thighs (she loved it when Alphys did that). Alphys squirmed a little in anticipation, licking her lips, and Undyne felt her tail wag all on its own, as if betraying her excitement.

Then, she leaned down and slid her tongue slowly along those folds, hesitating only a little when she realised how strange this was, seeing herself this close up. She actually wasn't that bad, and she felt herself blushing a little, especially when she registered her own taste. It also wasn't too bad, but her body immediately flooded with desire the moment that happened, and she allowed that to distract her.

Alphys shut her eye tight, one hand at her breast, the other buried deep into her hair. When she felt Undyne lick her, she exhaled sharply, surprised.

When Undyne suddenly buried her tongue deep within her, she cried out in shock, jolting up and opening her eye wide, feeling a wave of lust crash into her. "Ah!" she cried, grabbing onto the bed beneath her. "Oh my _god! Oh my god! Undyne!"_

"Mmhmm?" Undyne replied, sounding amused. She pulled back a little, just for a moment, and when Alphys was about to speak, she dove back in, turning her words into a strangled cry. She grinned; it was exactly how she felt any time Alphys did this to her.

On that thought, she slid her tongue up and circled Alphys's clit slowly, bringing a moan from her wife, before she stuck her tongue deep within her once more.

"Undyne!" Alphys cried, Her body starting to move along with her administrations, her eye shut again and her body breaking into a sweat. "Undyne, _Undyne!"_ It was all she could say, really: all she could even think about was her, and she was already so close again that it was unbearable.

Undyne increased the pace, knowing exactly what herself like, and Alphys was gone, so close that the sounds that came from her beyond her control, desperate to come, _needing_ to come, _having_ to come so dearly...

Undyne then jerked her tongue up and hit her clit hard, and Alphys keened out, her voice breaking as her orgasm struck her. She squirmed again, harder, her whole body overcome and her control completely gone. Feeling an orgasm in Undyne's body was different than feeling her own, it was true, but it was no less pleasurable. The major difference was that, instead of feeling dizzy and sleepy, she felt as if it energised her, woke her up, made her want more and _more_...

As it faded, Alphys fell back onto the bed, a sob coming from her throat, the sound slowly changing into a moan of longing. She reached down and grabbed Undyne's hands, pulling her from between her legs and on top of her so easily that it was amazing. Undyne was so strong that even someone built like Alphys was nothing to her. Undyne stumbled, clumsier, now, but she grabbed hold of Alphys for quick balance, using her tail to help her.

Alphys's mouth was on hers as soon as she was close enough, growling from deep in her throat as she thrust her tongue between Undyne's lips. Undyne returned it, wrapping her arms and legs around her and clinging onto her tight, a moan of her own escaping her.

"More," Alphys pleaded between kisses, her fingers digging into Undyne's back. "More, _more!"_

"Alphy...!" Undyne laughed.

"I c-can't help it!" Alphys cried, moving her hands to cup around Undyne's breasts - and feeling a little jolt when she realised just how nice that felt. She blinked and looked down, as Undyne shifted and closed her eyes, her claws digging into Alphys's shoulders a little. Her breasts were actually very soft, and felt oddly vulnerable in her strong hands. Yet her own body was awash in arousal at the mere action, and she found her thumbs flicking over already-hard nipples quite easily.

"Mm," Undyne murmured, pressing her forehead to Alphys's and closing her eyes. "That's... Mm! Alphy, holy _shit_ , I had _no_ idea...!"

Alphys nodded, then jumped when Undyne slipped her hands to her sides and slid her fingers over her gills slowly. "Oh god," she blurted out, gasping a little. "Yes, _yes!"_

"Alphy," Undyne suddenly whispered, her voice hoarse. "Touch me. I need you to touch me."

Alphys licked her lips and nodded, using her new strength to take hold of her and push her onto her back. She knew her own body as well as Undyne knew hers, and she immediately pressed her body alongside Undyne's, making sure that her legs remained around her waist. Undyne closed her eyes, flashing hot, and her fingers increased their trails along Alphys's gills, just as Alphys buried her fingers between Undyne's legs.

Undyne's eyes flared the moment Alphys touched her, the touch alone sending a flare of lust through her so strong that she reached up and clung to Alphys, closing her eyes tight and uttering a sharp cry. Alphys grinned, that sound oddly satisfying to her, and knowing exactly what to do, she slipped two of her fingers between Undyne's folds and deep within.

"Fuck!" Undyne yelped, her voice cracking; Alphys's aim was true, and her fingers touched in exactly the right place. Alphys leaned down and licked down Undyne's neck slowly, at the same time curving her fingers upward and rubbing the tips along that soft spot right on.

"Holy _fuck!"_ Undyne shouted, her claws digging into Alphys's back hard _. "That's_ what it feels like for you?! That feels _nothing_ like it feels for me! Holy shit, no fucking wonder you love this!"

Alphys laughed a little shyly, blushing, but she gently bit down, and Undyne squirmed with another cry, her tail reaching out and grabbing hold of Alphys's forearm tight.

"More?" Alphys wondered teasingly.

"Fuck yes!" Undyne growled, shifting her hips to drive Alphys's fingers deeper. "Go, go, _go!"_

Alphys laughed again, this time louder, and she started to rub her fingers slowly, drawing out each stroke. Undyne relaxed in her arms, her head tilting back and her eyes closing, a low moan escaping her. "Holy fuck, Alphy," she grated out between her teeth, her breaths more like gasps. "Holy fuck!"

"You have glorious fingers," Alphys replied. "I love it when you do this to me."

"Fuck!" Undyne answered. "I'll never stop, if it makes you feel this good! _Shit!"_

Alphys swallowed yet another laugh; whenever Undyne was consumed by her desire, she swore even more than usual. It always made Alphys happy, as it was an easy indicator that she was enjoying herself.

"Harder," Undyne suddenly growled, arching up so that Alphys's fingers hit deeper. _"Harder,_ Alphy! I'm already _so fucking close!"_

Alphys was surprised by that, until she really thought about it. She kept forgetting that this was her own body, and Undyne was her greatest joy, so thus it wasn't all that surprising, really.

With that in mind, Alphys pressed closer, angled her wrist, and drove her fingers in deeper - and faster. Undyne grinned with a surprised laugh, one that turned quickly into a desperate keen. She dug her heels into the bed, her hands scrabbling at Alphys's back as her body started moving alongside each thrust, her body already breaking into a sheen of sweat.

"Oh shit!" Undyne suddenly cried, sitting up and burying her hot face into Alphys's neck, her teeth sinking into the curve so sharply that Alphys shivered. "Shit! _Shit!_ Alphy! _Fuck me, Alphy! Ah!!"_

After that, anything that escaped Undyne was incoherent, save Alphys's name - and even then, it was thick and high-pitched, choked with increasing need. She was so close, it was absolutely unbearable.

When Alphys suddenly jerked her fingers up and pushed her thumb down upon her clit, that was it for Undyne. With a loud shout that almost hurt her throat, she came hard, her whole body shaking from the force of it. Undyne was dazed, overcome with how amazing it felt. When Alphys came, it was _hard_ , and suddenly, Undyne found herself breathless, her eyes squeezing shut tight and her mind going blank, save that delicious pleasure.

"Undyne!" Alphys called gently, recognising this and feeling a tinge of worry, despite knowing better. Undyne suddenly relaxed against her, panting so hard that it shook her entire body, and she leaned heavily in her arms. Alphys slowly pulled her fingers free, and Undyne clung to her, shuddering and moaning softly, feeling both amazingly high and oddly weak.

"Hon?" Alphys murmured, reaching up and touching her cheek gently.

 _"Hnngh,"_ Undyne answered, her voice tiny. She had wanted to actually say that she was fine, but that was all she could get out.

"Good?" Alphys wondered, kissing her forehead gently.

"Fuck," Undyne agreed weakly, nodding and nuzzling her hand.

Alphys gave her a moment, rubbing her back slowly with her other hand, keeping the other upon her cheek. Undyne eventually calmed, and she smiled, her eyes still closed and her body still resting limply against her.

"Wow, Alphy," she murmured, sounding dazed. "Just... wow."

Alphys nodded in agreement. "Like I said: you have amazing fingers."

"I had no idea," Undyne admitted. "I mean, I knew you liked it, but I didn't know it felt like _that."_

"Now you know," Alphys replied.

"Mm..." Undyne buried her face into the crook of Alphys's neck, circling her arms around her neck shortly after, sighing deeply. Alphys held her close, lying them both down onto the bed and holding Undyne to her. "Alphy..."

"Yes?" Alphys said.

"I love you."

Alphys smiled, closing her eye and resting her cheek atop Undyne's head. "I love you," she replied.

Undyne sighed again, shivering in delight, and Alphys held her close. In moments, Undyne had drifted off into a doze, and it didn't take long for Alphys to follow.

They slept for a few hours, a heavy sleep of the deeply satisfied. When they awoke slowly, they realised, quite suddenly, that they were back in their own bodies again.

Their eyes met, both sharing a mix of relief and disappointment, but they both smiled. After a moment of gentle kisses and caresses, Undyne whispered, "Alphy, make love to me, please."

Alphys smiled up at her, nodding. "Yes, please," she agreed.

With the knowledge they'd learnt from their own bodies, they were eager to apply it, and as a result, they both admitted after, it was honestly the best sex they'd ever had up to that moment.

But it wouldn't hold the record - that was for certain.


	7. Cross-Dressing

**Notes for the Chapter:**

> This one is a little short, and doesn't get into the sex, as I'm currently in a hurry but want this up in time. I may edit this later, though, to include the sex, so keep an eye on it! (If I do, I'll make note of it in later chapters, as well as repost it on Tumblr, but right now, I doubt I will unless you all really want it.)

"Hm..."

Alphys looked up from her book curiously; Undyne was sitting at her desk, her eye on the screen of her laptop, and she looked like she was examining clothes. Alphys looked back down, as this wasn't unusual, but Undyne wasn't finished.

"Hey, Alphy," she said, getting her attention once more. "Have you ever worn a suit before?"

Alphys blinked at her. "Uh, a suit?"

Undyne nodded, turning around to look at her, her hand gesturing to the screen. Alphys stood up and walked over to get a closer look, and found that Undyne had been looking up men's clothes, and was on the formal section.

"Oh, those kinds of suits," Alphys concluded, blinking at them. "I don't think any of those would fit me, Undyne. They're shaped for men."

"I bet I could find you one that fits," Undyne replied with a mischievous grin, turning back to the screen, already typing.

"Why?" Alphys answered, confused. "I don't need a suit. I have my coats."

Undyne was silent, her eye going over the screen, but Alphys noticed that she was starting to blush. Alphys leaned closer, and Undyne turned her head, her blush deepening.

"Undyne?" Alphys added, confused.

"Uh, well," Undyne stammered, sounding shy. "I-I kinda wanna see you in a man's suit."

Alphys tilted her head at her. "Why?" she repeated.

"Because it would be..." Undyne scratched her cheek. "Hot."

Alphys stared at her. "Hot? Me in a suit?!"

Undyne nodded, her eye flicking up to look at her, still shy. "Yeah," she agreed. "Every time I picture it, I..." She smiled. "I like what I see."

"But reality isn't as kind," Alphys said flatly. "There's no way I can fit into one of those."

"I bet you I could find you one that fits you so well, you'd love it," Undyne countered.

Alphys raised her eyebrows. "You're on. If you win, you get to take me out and see if people think I'm a guy. If I win, I never wear it again and we return it to get our money back."

Undyne's grin widened to one of delight. "You're on!" she agreed happily.

Alphys laughed, quite certain Undyne would fail, and with a kiss to her cheek, she sat back down and resumed reading.

She was very, very wrong.

* * *

"Oh, Alphy...!"

Undyne walked into the house, singing the words as she jumped in and kicked her boots off. Alphys looked up from her desk, glad to be interrupted from grading papers - and blinked.

Undyne was holding a huge package in her arms, grinning so happily that her eye was a crescent.

"Is that...?" Alphys wondered weakly, pointing at it.

"Fuck, yeah!" Undyne agreed. "C'mon, get it on, get it on!" She tossed it towards her wife, who caught it - then dropped it by accident, bringing a deep blush to her face. Undyne, however, laughed and picked it back up, then took Alphys's hand and pulled her to her feet. With a smile, she allowed herself to be dragged to their bedroom.

When Alphys was dressed only in her underwear and a camisole, Undyne opened the box and revealed the suit. It was actually rather beautiful, the material soft and teal-coloured, and Alphys eyed it with sudden interest.

Undyne laughed, catching glimpse of that look, and she tossed the slacks to her. This time, she caught them fine, and she held them up for a moment, unsure. "Undyne," she murmured, "are you sure this'll fit? I don't want to rip this, in case we need to return it, and my tail--,"

"Put it on," Undyne answered. "There's a space for your tail, I made sure of that. Put it on!" She couldn't help her excitement; it was less about dressing Alphys up into a man, but more like seeing a side of Alphys that she'd never seen before. Therefore, she was excited, and it showed.

Alphys noticed that excitement, and with a shy smile, she carefully started to get dressed. Undyne watched sharply, sitting on the bed and bouncing a little, grinning.

To Alphys's surprise, the suit actually fit her rather well - almost shockingly well. Granted, the sleeves were probably too long, and the coat wouldn't close over her breasts too well, but for the most part, it fit.

"Well," she concluded, touching her sleeves a little shyly. "I guess I'm going out as a man today."

Undyne was staring at her, her face bright red and her eye wide, her grin almost wild. Alphys, to her, looked stunning in that suit. It wasn't just the colour, though that was perfect for her wife's skin tone, but the way it fell on her body. It softened her curves, gave her straighter lines, and yet in other ways it seemed to call attention to those curves, too. Alphys looked boyish, it was true, and she probably could pass as a man if she bound her breasts, but Undyne suddenly realised she didn't want that at all. She wanted Alphys to look exactly like this: androgynous and fancy.

Alphys eyed herself in the mirror, moving from side to side and trying to get a decent look at herself. "Hm," she said softly, looking surprised. "This is pretty nice, Undyne. I'm sorry I doubted..." She looked up and finally noticed Undyne's expression, and her blush went scarlet in surprise. "...you?" she concluded, her voice squeaking a little.

"Alphy," Undyne replied, her voice husky, her hands clutching at her knees hard. "You're so _fucking gorgeous."_

Alphys lowered her head, feeling her whole body flush with shyness, and she shifted a little, her hands tangling in front of her. "I-I wouldn't go th- _that_ far..." she admitted.

Undyne got up and was in front of her before she could even raise her head. She stared up at her, noticing that Undyne's face was red, too - and her eye gleamed. She knew that look well, by now, and felt her body react to it with surprise.

"I mean it," Undyne answered, reaching down and cupping Alphys's face between her hands. "Fuck the bet," she added. "I don't want to go anywhere. You're too fucking hot to share right now."

Alphys laughed, looking away for a moment, but Undyne leaned down and kissed her lips, the kiss lingering so sweetly that Alphys had to grab onto her forearms to stay standing, her eyes fluttering closed. Undyne moved closer, sliding her arms around her waist, before she abruptly picked her up and off of her feet, causing her to break the kiss and splutter out a sound of surprise. But Undyne kissed her again, and Alphys reached up and clung to her - including slipping her legs around her waist and gripping hard.

They stayed in that night, not leaving their bed save for food and the washroom. Alphys, it must be noted, kept the suit on for most of the night, though Undyne, herself, wore absolutely nothing, adoring the feel of clothes so neat and tidy against her naked skin. Alphys in turn was oddly aroused by this, too, and definitely took advantage of it, at one point wearing nothing but the coat of the suit - which Undyne absolutely loved.

They certainly got their money's worth, at the very least.


	8. Face-Sitting

"Mm..."

This was probably Alphys's favourite sound, one only Undyne could make, and only when she was feeling pleasure from her, alone. It always made her happy, and her tail wagged before she even thought about it, nuzzling her face closer and licking deeper between Undyne's folds.

"Hey."

Alphys blinked and looked up, surprised; Undyne was sitting up, propped up on her elbows, and while her face was red, her eye was suddenly focused.

"I have an idea. You can say no, of course, but..." She blushed deeper, and Alphys nodded, suddenly intrigued. "Can I... uh... can I... try, uh... s-sitting on you?"

Alphys felt her face burn, her eyes widening at the very thought. Silently, she pulled away quickly and moved to lie down, nodding and holding her arms out. Undyne burst into laughter, both in shyness and relief, and she sat up and moved over to her, biting her lip. Alphys smiled wider, feeling her heart speed up, and she waved her hands at her wife eagerly.

Undyne hesitated, but just for a moment, before she grinned and leapt atop of her, straddling her chest for a moment, before Alphys grabbed her hips and pulled her up. She propped herself up on her hands to start, but the moment she was close enough, Alphys started licking her again, and she growled, relaxing and closing her eye.

Alphys closed her eyes, holding onto Undyne's hips tight as she licked slowly along her folds, before diving her tongue deep within. Undyne cried out, arching back and placing her hands on her knees instead, and Alphys purred, loving that Undyne was now not only closer, but relaxed enough to abandon herself to it.

"That..." Undyne grunted out, feeling heat fill her and her body start to move along with Alphys's tongue. "... _fuck_."

Alphys giggled a little, her tail thumping happily, and Undyne squirmed, the sound more felt that heard. She slipped her tongue up and focused on her clit, and Undyne gasped, her body jerking and her thighs tightening a little around Alphys's cheeks.

"Shit," Undyne murmured, her voice small, now. "I'm... already close... _don't stop!"_

Alphys had no intentions of stopping, anyway, and she circled her tongue around Undyne"s clit slowly, occasionally dipping her tongue down within her before dragging it back up slowly. Undyne hissed out, her body jerking a little, but she matched Alphys's pace and was rewarded immensely for it.

"Yes... _fuck, yes..."_ Undyne growled, unable to keep herself quiet - not when it felt this good. "Alphy, holy _shit_..."

Alphys, in return, increased the pace, and Undyne cried out, leaning forward and falling back down hard on her hands, struggling to keep up but loving every second of it. She grinned, her breaths short and raspy, and she barely managed to groan out her wife's name before she came, hard, staggering atop her but still moving, wanting it to last. This was no issue for Alphys, judging by how easily she met her pace and how happily her tail wagged.

When it started to fade, Undyne collapsed to the side, gasping for breath, and Alphys sat up and grinned down at her, licking her lips. She leaned down and hugged onto Undyne tight, something Undyne felt with lingering pleasure and melted into.

"That was very nice," Alphys murmured into her ear, making her shiver.

"That's... putting it mildly!" Undyne agreed, her voice barely above a whisper.

It wouldn't be the last time - that was for certain.


	9. Lingerie

"U-uhm."

Undyne nodded, her eye glued to the screen in front of her. Alphys stood behind her and out of sight, but she was too focused to look just yet.

"Er, Undyne...?"

"What's up, Alphy?" she replied, her voice tight with concentration. She was just about to reach the final boss, and she wanted to make sure her team was fully equipped and ready to face it - and hopefully make it out alive.

"Uhm, w-well... I-I did something silly, and-and I was hoping you'd l-like to see wh-what it is."

"Of course I would," Undyne replied easily. Shit, one of her mages was low on magical herbs. She needed to fix that, and it was a pain in the ass...

"O-okay, well... uh..." Alphys fidgetted behind her, her whole body hot and her face bright red. "T-turn around?"

"One sec," Undyne said automatically.

"It-it's important..."

Undyne blinked, surprised by Alphys's tone: small, but serious. She paused the game and turned around - and froze, her mouth open and her blood rushing to her face - and between her legs.

Alphys stood shyly, shifting from foot-to-foot, but she met Undyne's gaze, smiling a little. She rather liked Undyne's reaction, after all.

And who could blame Undyne, really? Alphys wasn't wearing what she last saw her in - far from it. In the place of shorts and a tank top was a set of lingerie, one that Alphys wore rather comfortably, if she were being honest. It was made of lace, leaving generous gaps here and there, and trailing from the snug push-up bra was a sheer curtain that hung to her waist, open in the middle. The underpants were high-cut and rather modest, showing a great deal of her rear, but that also made her tail fit through easier. It was black, and it was a shocking contrast against her yellow skin.

"U-uhm," she murmured, looking at her feet shyly. "D-do you... l-like it?"

"Alphy," Undyne whispered, her heart racing. "Holy _fuck."_

Alphys looked up, surprised, but it didn't end there. Undyne leapt to her feet and grabbed her, pulling her off of her feet and pinning her against the wall, kissing her lips so hard that Alphys murmured softly. Undyne grabbed her legs and wrapped them around her waist, her tongue slipping out and darting into Alphys's mouth quickly. Alphys's eyes fluttered closed and she returned it, her claws digging into Undyne's back hard.

"I want you," Undyne gasped out after a moment, her hands already cupping around Alphys's breasts. "I want you _now."_

"You have me," Alphys answered instantly.

They didn't leave that wall for a long, long time.


	10. Knifeplay

**Notes for the Chapter:**

> This chapter gave me so much trouble, hence why it's so damned late. I'm gonna catch up, I swear!

It was Undyne's idea.

Alphys was wary around knives. She'd used them in medical school, sure, but she'd also used them on herself - and not for medical research.

But that, Undyne explained, was the point.

"You see them as something horrible and negative," she explained gently, rubbing Alphys's pale cheek gently. "But they can actually be really sensual."

Then, Undyne blushed, confirming something that Alphys had always suspected of her, long before they dated. "I really like swords and knives," she admitted. "They're awesome."

Alphys smiled a little, finding her shyness adorable. Still, she had some trepidation. "I don't want to hurt you."

"You won't," Undyne promised. "I'll tell you if you even get close to that. Plus," and here she flashed her grin, "I'm tough! I can take a lot before bleeding!"

Alphys laughed, finally feeling better about it, as she knew it was true.

"And," Undyne suddenly added, her eye softening. "I trust you."

Alphys bit her lip, nodding. That, she knew, was the most important part.

So when Undyne handed her the small knife, Alphys took it without much hesitation, looking at it closely. She smiled; it was one of those blades they'd both seen on the internet, a rainbow-bladed knife with a black handle. She touched the edge of it lightly and found that it wasn't that sharp, and she sighed with a bit of relief. She didn't want to cut Undyne because she underestimated its sharpness.

Undyne watched her closely, shifting a little in place beside her. She was excited, really: seeing Alphys holding the knife at last was definitely exciting, and she was glad she'd finally had enough courage to ask. She'd had the knife for months.

"This is pretty," Alphys murmured. "I like it."

Undyne smiled wider, leaning close and nuzzling her cheek gently with her own. Alphys smiled and kissed her, and Undyne returned it, reaching up and cupping Alphys's face between her hands. Alphys in turn shifted closer, and Undyne shivered a little, feeling excitement creep up on her.

"Alphy," she murmured, "cut off my clothes, please."

Alphys blinked at her, surprised; but then, she noticed that Undyne's clothes were actually rather worn. With a smile, she realised that Undyne had indeed hoped she would say yes.

She leaned down and nuzzled the crook of Undyne's neck, one hand reaching forward with the knife. She kept her eyes open, making sure her aim was true, and that she would only hit clothes. She used her other hand to lead her, and soon, with an oddly satisfying ripping sound, she had managed to tug the knife down and cut open the front of Undyne's shirt, from neck to waist.

Undyne shivered, feeling the cool of the blade followed by the warmth of Alphys's other hand upon her skin, and she sighed, leaning back a little.

Alphys then murmured, "Lie down?"

Undyne grinned at her, nodding and lying on her back. The now-ripped shirt fell open, and Alphys paused, leaning back to appreciate the sight. She could just see Undyne's breasts, the curve of which was mostly hidden, still.

Their eyes met, and they both shared a look of aroused excitement.

"Oh," Alphys whispered, blushing a little, and Undyne chuckled. Alphys smiled, moving closer to her, before she raised an eyebrow and sat down right in her lap. Undyne grunted in surprise, but still grinned, so she took that as a good sign.

Undyne took hold of her hips and gripped tight, making Alphys giggle shyly and shift closer. Gently, she placed the knife against Undyne's chest, between her breasts, and Undyne's eye flared, her smile curling wider. Alphys hesitated, then trailed the flat of the blade along the curve of one breast, using the blade to push the shirt apart.

"No," Undyne murmured, making Alphys freeze immediately. "Chill," she added. "I was just gonna say: rip the shirt off, Alphy. Don't be shy."

"O-oh," Alphys blushed, then nodded. With a slightly crooked smile, she took hold of the shirt in one hand, then used the knife to rip it again, this time cutting the sleeve off. Undyne grinned, shrugging the sleeve off and tossing it to the floor, and when their eyes met again, Undyne nodded in return, replacing her hands on Alphys's hips.

Alphys did the same with the other, and Undyne tossed that aside, too, feeling her heart start to speed up. Alphys trailed the flat of the rainbow blade along her upper arms, tracing her defined muscles slowly, and the cool of the blade felt so good upon her hot skin that she closed her eye.

Then, she slipped the knife behind Undyne, pressing it flat against her back, before she jerked her wrist up and ripped it open. Undyne jerked, surprised, but Alphys didn't pull away until it was completely sliced in half. Undyne felt her breaths increase alongside her arousal, and she stared at Alphys, yearning filling her so strongly that she shivered.

Alphys pulled the ruined shirt off, a side at a time, and tossed it aside, leaning down to kiss Undyne's lips gently, placing the blade flat and between Undyne's breasts. Undyne reached up and grabbed Alphys's face between her hands, kissing her harder, and Alphys closed her eyes for a moment, loving that.

As they kissed, Alphys slid the knife to the side and moved it slowly over Undyne's breast, making sure to keep it flat and the sharp edge tilted away from her skin. Undyne buried her face into her neck, her eye shutting in surprise, and Alphys held her closer, moving the knife over her already-hard nipple slowly.

"Shit," Undyne hissed out. "That's _hot."_

Alphys giggled, feeling her confidence increase, and she slipped the blade to her other breast, making sure the blade lingered over her nipple, not moving it until it was hard.

"Mm," Undyne added, biting the curve of Alphys's neck gently.

"You're so cute," Alphys blurted out.

Undyne went bright red, then tried to hide her face, but Alphys giggled again and kissed her cheek.

She kept the knife in place, letting go of it to take her own shirt and bra off, then stood up and wiggled out of her pants and underwear. Undyne watched her, licking her lips and taking the sight in with happiness, and the moment Alphys was sitting on her again, Undyne's hands were back on her hips at once.

Alphys smiled, then reached down and pressed the blade against the waistband of Undyne's pants. Undyne swallowed, but her eye blazed as she nodded. Alphys shifted to the side and off of her lap, then moved the knife and started cutting away Undyne's pants. Undyne watched her closely, noticing a glint in her eyes that she hadn't seen before - but rather liked. She felt Alphys's other hand trail over her skin as she cut those pants away, trailing her fingertips over it the moment it was exposed.

"Mm," Undyne whispered again. Her breaths were shaky, and her hands dug into the bed beneath her.

Alphys smiled, tugging the tattered remains of those pants off and to the floor with the rest. Then, she hesitated, her hands hovering over Undyne's underwear, for so long that Undyne looked up at her questioningly.

"Uh," Alphys said, noticing her look. "These, too?"

"Yes," Undyne agreed immediately, nodding. "Yes, please."

Alphys nodded, slowly sliding the flat of the blade down from the middle of Undyne's chest to the top of her underwear. She slipped the blade beneath, then jerked her wrist and ripped them, first on one side, then the other, and Undyne's skin broke out in gooseflesh.

Alphys smiled, tugging the now-two pieces of underwear off and adding them to the pile. With a look to Undyne, who was lying back with her eye closed and a smile on her face, Alphys trailed the blade very gently over the soft hair covering her, and Undyne inhaled sharply, feeling her heart racing even more.

"Alphy," she murmured weakly. "I need you."

Alphys looked up, smiling and feeling her heart jump, like it did every time Undyne said that, and she moved back up, pressing along her body with her own and kissing her deeply. Undyne purred and grabbed hold of her, grabbing the wrist of the hand holding the knife tight. Without pausing, she pulled her hand up and gripped it firmly, then slammed the blade into the headboard right above her head. Alphys jumped, then let go of it to wrap herself around Undyne tight, her hand reaching between them gently. Undyne shifted, and Alphys did the same, their legs tangling together. Their flesh met, and with a shared sigh, they kissed again, and Alphys started to move.

"Alphy," Undyne whispered after a moment, her voice hoarse. "Grab the knife again."

Alphys hesitated, her eyes opening and meeting hers, confused. "Wh-why?"

"Trust me."

Alphys of course did, so she grabbed it and pulled it from the headboard. Undyne grabbed her wrist again, pulling it down between them, and she pressed Alphys's hand between her breasts again, making sure the flat of the blade touched her skin. "Yes," Undyne whispered, the cold of the metal and the slight-sting of the edge sending a jolt through her body. "Keep it right there."

"O-okay," Alphys agreed, her voice small. Her eyes closed, and she tilted her head back, her body moving faster. She kept the knife where it was, and soon, Undyne grabbed hold of her upper arms, her head thrown back and her hips jerking up hard to meet Alphys's every thrust.

Undyne was already incredibly turned on, and the feel of that cold metal pressed against her racing heart only made that feeling more intense. Alphys had barely started before she felt her control start to wane, and she clung to her, urging her to go faster with anything but words - but still loud. Alphys held her close, easily complying, as she, herself was incredibly worked up, as well - something that actually surprised her.

 _"Alphy,"_ Undyne managed to groan out, her eye shut tight, before she jerked close, her teeth grazing Alphys shoulder, and started shaking, her cries escalating the closer she got. Alphys shuddered, unable to even say Undyne's name, her eyes locked on Undyne's face, loving to watch her come.

And Undyne finally was. She cried out, her hips pushing up hard, and she came, hard, making sure Alphys kept that knife in place as she did. It swept over her, so sweetly that she laughed faintly, and Alphys kissed her, entranced by it all.

When Undyne calmed, Alphys slowed down, thinking that perhaps she should stop, in case Undyne was too tired to continue. But Undyne wasn't done, not until Alphys was, and when she could, she grinned and pulled Alphys close again, urging her to keep going. Alphys grinned this time, burying her face into Undyne's shoulder before she started moving again. Undyne's eye closed, feeling faint ripples of aftershock flow through her, ones that increased as Alphys's body's moves increased against her.

Alphys then let go of the knife to reach up and grab hold of Undyne's shoulders, her hold breaking loose. She cried out, then fell into it, surrendering to that sweet release and loving everything about it - especially Undyne.

Undyne kissed her gently as she relaxed against her, shivering and murmuring nonsense against her lips. Undyne laughed, reaching between them to push aside the knife, before she pulled Alphys closer to her. Alphys relaxed, feeling wonderfully boneless, and Undyne laughed softly.

Then, Alphys whispered, "That was... interesting."

Undyne laughed louder at that. "It was!" she agreed. "And fun! Hell, Alphy, you're so _fucking hot_."

Alphys giggled tiredly. "Me, or the knife?"

"Both, definitely," Undyne decided.

"Hm," Alphys replied, her tone thoughtful. She reached over and grabbed it again, holding it up and allowing the light to shimmer over it, loving the colours.

Then, with a devious grin, she looked up at Undyne and placed the knife flat against one of her breasts, before moving it slowly over to her nipple. Undyne shivered again, her eye closing, before she shifted, bringing her legs up and wrapping them around Alphys's waist.

"Again?" Alphys wondered.

"Fuck, yes," Undyne agreed.

It was a productive evening.


	11. Orgasm Denial

Sometimes, Undyne drove Alphys insane.

Case in point: They had the afternoon off, as the school only had a half-day for a holiday, and the two immediately ditched work and ran home, eager to spend the hours at home and together - especially intimately.

Undyne loved pinning Alphys to walls. She loved the feel of it, the fact that she could do so much to her in such a silly way, and it always turned her on. Alphys, in turn, loved to be pinned to walls, always adoring Undyne's strength - as well as her attention to detail.

Today, however, Undyne was being mischievous, and very much wanted to tease Alphys. Alphys, oblivious to this at first, simply thought she wanted to have sex against the wall, and when she was pinned and kissed, clung to her wife immediately and returned both gestures, her claws digging into Undyne's shoulders hard.

Undyne reached between them and buried her hand beneath Alphys's pants, her fingers reaching and slipping between hot and slick flesh. Alphys gasped, arching a little to bring them deeper, and Undyne grinned, licking along Alphys's neck slowly.

When she drove two fingers in deep, Alphys cried out, the sound quickly followed by Undyne's name, and Undyne felt a thrill go through her. She worked her fingers faster, making sure the tips hit that spot every time, and soon, Alphys was begging her to move faster, harder, whatever it took to make her come.

And yet, the moment Alphys felt herself about to, Undyne pulled her hand away and grinned. Alphys gasped, her eyes snapping open in shock and her whole body shuddering, and Undyne merely met her gaze, licking her fingers slowly.

"Undyne!" Alphys cried, her voice hoarse. "Don't stop! Keep going, I was so close!"

"Oh?" Undyne murmured, her expression anything but confused. "Okay, then." She reached down and took hold of Alphys from the back of her knees, gently setting her down to pull her pants down and off, and Alphys took the same time to throw her shirt and bra off, too. When Alphys was naked, Undyne grabbed hold of her again, only this time, she hoisted her up and went down on her knees, burying her face between those wonderful thighs and licking along those folds slowly, relishing in the taste.

"Ah! Undyne!" Alphys cried, her hands going right to her hair and tangling within it. Her heels dug into Undyne's back, and she leaned against the wall, her eyes closed and her face red. "More, please?"

Undyne chuckled, a sound she felt, and moved closer, sliding her tongue slowly upwards towards Alphys's clit, lingering there and feeling a thrill when Alphys cried out and started shaking against her, her body moving alongside each flick of Undyne's tongue.

 _"Yes,"_ Alphys whispered, her voice breaking. "Yes, I'm _so_ close... _don't stop!"_

Undyne, however, smirked, and pulled away abruptly.

Alphys stumbled in shock, her eyes flaring open and going to Undyne, her whole body shaking with that same shock. _"Undyne!"_ she cried. "Why did you stop?! I was so close, _please!"_

Undyne smiled up at her. "How badly do you want it?"

Alphys stared at her. "Undyne, you _know_ how much!"

Undyne moved slowly away, helping Alphys back to her feet, before catching her, as she almost tumbled from her trembling. Alphys stared at her, confused and burning with need, and Undyne grinned.

"Say it," Undyne replied.

Alphys blinked hard, trying to get her brain to focus. She reached forward, grabbing hold of Undyne's shirt and pulling on it desperately, trying to pull It off, but Undyne didn't budge.

"Undyne," she pleaded, still tugging helplessly at her wife's shirt, her hands clumsy. "Please, I need you, _please?!"_ Her voice broke, but them something flashed in her eyes, and Undyne only had a few seconds before she was tackled to the ground and pinned to it, Alphys kissing her so hard and pressing her body so closely against her that she groaned, holding onto her tight.

"Please," Alphys whispered between kisses, giving up on the shirt and going right to Undyne's pants. "Please?" It was all she could say, she discovered.

Undyne nodded, pulling back and getting undressed quickly, before Alphys pressed down and pinned Undyne to the floor again, wrapping her legs around Undyne's waist. She grinned, especially when she saw Alphys's eyes shine with need, and she wasted no time, shifting her hips up and rubbing her own slick flesh close against her wife's. She then rolled Alphys over, so that she was the one pinned once more, and Alphys clung to her, a sound of pure satisfaction escaping her. She urged Undyne to go faster, still teetering on the edge and desperate for release.

Undyne smirked again, something Alphys missed; she was too caught up, too desperate. When she felt her control start to vanish, she cried out Undyne's name and dug her claws into her back.

And that's when Undyne suddenly pulled away and sat up.

Alphys tried to follow her, her voice breaking with her shock and dismay, but she tripped and stumbled. Undyne caught her, but Alphys was too stunned to do anything more than gap at her, her whole body shaking.

 _"Undyne!"_ she cried, her voice breaking. "Wh-why are you--? Do you n-not want to? What am I doing wrong?"

Undyne shook her head, smiling. Alphys stared at her; the smile was hungry - and teasing. "You're not doing anything wrong," Undyne admitted honestly.

"Undyne," Alphys growled out, her voice wavering. _"Stop_. Please stop. _Please_ stop torturing me! Please, I need you, I _need_ you _so much!"_

"How much, Alphy?" Undyne wondered, leaning close and whispering it, making Alphys shiver and reach up to grab hold of her shoulders.

"So much," she whispered, trying to crawl into her lap. Undyne smiled and moved away, and Alphys stumbled again.

Then, the thing Undyne wanted most finally happened: Alphys lost her composure, and with a cry of desperation, she threw herself at Undyne and tackled her to the floor again, wrapping her body around her tightly and pinning her hands down by the wrists.

 _"Undyne,"_ she growled, leaning down to kiss her so hard that Undyne was the one moaning, now. But she nodded, so Alphys added, her voice cracking again, "Please, _fuck me!!"_

Undyne shivered, grinning, and without a word, nodded. She tried to free her hands, but Alphys kept them pinned, so she bent her legs and dug her heels into the floor for balance. Alphys kissed her again in that same hard way, at the same time pushing her hips down and sliding her flesh against Undyne's, and this time Undyne purred, slipping her tongue out to meet Alphys's.

Alphys was still on the edge and wild with need, and she moved hard and fast, with a fervour that surprised Undyne - but in a pleasant way. _"Yes,"_ she cried against Undyne's lips, her claws digging into Undyne's hands a little. Already she was so close, and already her body was losing control. She growled again, making sure Undyne was pinned and unable to move away, and when Undyne merely met each thrust and kept her close, Alphys finally relaxed - and let go.

She came hard, so hard that she practically shouted Undyne's name, so loudly that it strained her voice a little. She staggered above Undyne, arching back and saying her name over and over, completely overcome after being held back for what felt likes so long...

When it started to fade, Alphys collapsed atop Undyne, gasping for breath, her whole body trembling and covered in sweat. She buried her face into Undyne's neck, murmuring softly in both relief and affection, and Undyne pulled her hands away to hold her close, comforting her.

Then, Alphys said, her voice sharp, "You're _mean!"_

Undyne laughed; her tone was so indignant that it was actually very cute. "Sorry," she replied, rubbing the back of Alphys's head gently. "But... you're so cute when you're horny!"

"Mean!" Alphys repeated, but her tail wagged a little, an idea coming to her. She raised her head, her eyes meeting Undyne's, and suddenly Undyne swallowed hard; Alphys's grin was just as devious as hers had been from the start.

"We're _not_ done," she added, and Undyne grinned at her.

"Bring it on, love," she answered.

It was a challenge, one Alphys easily met - and certainly more times than Undyne had with her.

It was the best revenge, they both agreed after.


	12. Handjob

Often, the mere sight of Undyne's fingers sent Alphys into a daze of lust, and usually at the most inappropriate moments, too.

One in particular stood out amongst many others, and that was when, one evening, Undyne was practising on the piano, as she usually did every night for at least a half-hour. Alphys loved it, as she loved listening to her play - and sing, sometimes - no matter how many mistakes she made or how loudly she cursed.

This night, Alphys was watching her keenly, affection sweeping through her so deeply that she felt her body heat up, a smile playing at her lips. She stood up from her desk and walked over to her, and Undyne smiled, not pausing but nodding to her. Alphys sat down beside her and watched her play, her hands carefully folded in her lap.

Undyne had beautiful fingers. It was one of the first things Alphys had noticed about her. They were long, and calloused from years of weapons training, but their nails were always clean and cut short, so that they wouldn't interfere with both training and piano, as well as get broken and annoy her.

Alphys loved them. She loved how strong Undyne's hands could be, and she also loved how gentle they could be, too. When Undyne touched her, she felt it all throughout her body, and she adored her for that.

Now, however, in between loving to hear Undyne sing and play, she couldn't help but notice how agile those fingers were, how easily they danced over the keys. Her eyes were locked onto them, and suddenly, she felt horribly aroused, thinking of other ways that Undyne could put those fingers to use.

She tried to hold back, knowing that Undyne very likely wouldn't appreciate an interruption, but the longer she watched, the harder it became. Therefore, it was with little thought that she suddenly reached forward, grabbed one of Undyne's hands, and pulled it to her, causing Undyne to stumble over the keys in surprise, her other hand playing nonsense notes as a result.

Before she could even ask, Alphys moved closer and pulled Undyne's hand beneath her pants and underwear, her eyes closing the second her fingers touched her skin. Undyne jolted, her face going red, before she suddenly grinned, turning all of her attention to her wife, now.

"Really, Alphy?" she teased, slipping her fingers slowly along her folds, delighted by how slick they were.

Alphys nodded, leaning closer and keeping hold of her forearm tight. Undyne laughed but moved closer, sliding her other arm around Alphys's waist, and she slowly started to trail her fingers along Alphys's slit, sneaking her fingers up every once and a while to touch her clit.

Alphys leaned forward, pressing her forehead to Undyne's shoulder, her hands grabbing hold of her shoulders in a grip so hard that it sent a spike of arousal into Undyne.

"Yes," Alphys whispered, her body starting to move along with Undyne's touches.

"You're so fucking adorable," Undyne concluded, before she pulled Alphys right up to her, sending her fingers deep within Alphys as she did. Alphys uttered a small cry, the sound thick with longing.

With a grin, Undyne crooked her fingers up and found that one spot, that perfect button that, whenever she pressed it, had Alphys reeling and clinging to her - in more ways than one.

"Fuck," Alphys whispered, surprising her, but when she looked at her wife's face, she saw how red Alphys's face was, how tight her eyes were shut, and best of all, how she smiled, especially when Undyne started to move her fingers against that spot. "Undyne..." she added, her voice catching.

"Yes, my love?" Undyne replied, not even hesitating in her pace.

Alphys could only answer with a babbling of words, barely coherent. Already, she could feel she was getting close, and she dug her claws into Undyne's shoulders harder, her body swaying with each touch. Every touch felt incredible, so much better than she could ever do herself, as Undyne's fingers were far longer than hers - and definitely more agile.

Undyne knew what those sounds meant, and with a wider grin, she held Alphys around the waist tighter before she increased the pace. Alphys cried out, her voice catching again, and Undyne shivered in delight; not much was better than hearing Alphys's aroused cries.

"Undyne," Alphys hissed out, arching back and tilting her head away from her shoulder, her eyes still closed. "Harder, please, _harder!"_

Undyne immediately obeyed, and Alphys made a sound between a laugh and a hiccup, something that Undyne laughed at softly. Alphys barely heard it, instead hearing the sound of her own blood rushing fast through her veins, so close, _so damned close..._

Undyne then leaned down and bit her neck, right at the curve's soft spot, and Alphys was immediately overcome, drowning in that pleasant tide as she came. Undyne held her close, moving her fingers in such a delightful way that it drew it out, and Alphys laughed again, burying her face back into Undyne's shoulder and shuddering.

When she calmed, Undyne pulled her hand away gently, then gathered Alphys into her arms, kissing the top of her head softly. Alphys sighed deeply, curling up into her embrace, holding onto her still while trying to catch her breath.

Then, she whispered, "I love your fingers."

Undyne burst into laughter, so happy at this that she grabbed Alphys's face in her hands and peppered it with kisses. Alphys squirmed and giggled, pretending to try and escape, only to give up when her laughs took over.

After that, Undyne always kept an eye on Alphys when she practised the piano. More often than not, Alphys would stay in her seat, happy to listen. 

But sometimes, Undyne caught that same yearning look, and would gesture for Alphys to sit with her - only to start it all over again.


	13. Medical Play

**Notes for the Chapter:**

> Okay, so this is more like roleplaying than actual doctor kink, but dammit, it's the best for them, I think. It suits them better! Fight me!!

Alphys was Undyne's primary doctor, now. This was absolutely no secret to anyone, as Undyne proclaimed it many times, loving to brag about it, as it proved she trusted Alphys with almost every single aspect of her being. Alphys, in turn, was also rather proud of her trust, and did her best to make sure she never betrayed it.

She wasn't, however, prepared for just how deeply that trust went, until Undyne showed her.

Alphys had just finished Undyne's yearly check-up, and she gave her wife a kiss on the forehead, taking off her gloves and saying, "All done."

Undyne smiled. "Thanks, Doc," she replied. 

Alphys laughed, giving her another kiss, and Undyne grabbed her, surprising her. 

"Hey, Doc," she added, leaning close enough to press her forehead to Alphys's. Alphys blinked, confused. "I think I forgot to add something that's been bothering me."

Alphys felt a tinge of worry, and she nodded, sitting down on the cot beside her, the fold-out cot they used for guests, or moments like these. "Okay," she said softly, taking one of Undyne's hands into hers. "Go ahead."

Undyne's eye searched hers, suddenly realising that Alphys was taking her seriously. For a moment, she was stunned by a wave of affection for her, and she reached up and touched Alphys's cheek gently, smiling at her. 

"Alphy," she said, her voice as gentle as her touch. "I think I'm heartsick."

Alphys blinked, noticing how Undyne was looking at her and feeling confused. "Heartsick?" she echoed. "But I listened to it and checked your blood pressure--,"

Undyne leaned closer. "I'm heartsick whenever I see my doctor," she murmured.

Alphys suddenly blushed, getting it right away, and she blinked, shifting a little. "Er," she answered, tongue tied, now. 

"For someone with my condition," Undyne continued, still stroking Alphys's cheek gently, and Alphys nuzzled her hand, her eyes closing for longer than a blink. "What would you prescribe?"

Alphys looked at her, a small smile playing around her lips. "I would... I would recommend..." She giggled. "Undyne..."

"Tell me, Doc. Am I gonna die from this?" Undyne wondered. "Or do you have a cure?"

"Every time you look at your doctor, what do you feel?" Alphys wondered, reaching up and placing a hand between Undyne's breasts, right over her heart. She could feel its pulse, and feel how fast it was beating, and her face burned, shifting again.

"I feel dizzy," Undyne murmured, leaning closer and brushing her cheek against Alphys's, her eye closing. "I feel faint, and warm, and giddy. I feel like she could ask me to run around the world and I would do it twice, just to make her smile. I feel like I can't stop touching her, can't stop looking at her, and even when I do both, it's never enough. Most of all..."

Undyne took hold of Alphys, pulling her into her lap, before she lay back down with her wife atop her. Alphys moved closer to her, getting comfortable while staying close, and Undyne wrapped both her arms and legs around her, her eye blazing and her smile toothy.

"Most of all... I want to make her laugh, comfort her cries, and hear her sing," she concluded, her voice barely above a whisper, now. "What would you prescribe?"

"Marry her," Alphys replied, smiling in return. "Marry her, and be yourself, and she'll be happy. Never stop holding her, never stop touching her, and always be yourself. She'll be yours for life." She then giggled and added, "I also recommend at least four kisses and six hugs a day."

"Mm," Undyne replied, nodding in agreement, her hands reached between them to unbutton Alphys's coat. "Should I start treatment right away?"

"Oh, yes," Alphys agreed, shrugging her coat off once she could. "The sooner, the better."

"Kiss me, Doc," Undyne answered.

Alphys kissed her.

They didn't leave that cot for a long time after that.


	14. Sensory Deprivation

Undyne was blind and deaf, and she was thrilled about it. The blindfold covered her eye perfectly, and the earplugs Alphys had given her drowned out everything. All she could hear was her own breathing and her racing heart, and she squirmed a little, full of excitement and anticipation.

Alphys was taking her time, both shy and turned on and overwhelmed by both. They were both naked and in bed, and Undyne was lying down on her back, her arms at her side and her legs bent at the knees and shaking a little. Alphys wasn't touching her, not even a little, and that was the entire point.

Undyne was waiting, and the waiting was making her crazy. She yearned to be touched, to be caressed, to be kissed, but Alphys was taking her time, building it all up, and it was almost agonising.

Alphys eyed her wife closely, trying to think of what to do first. That first move meant everything, as it would be the most unexpected - and would likely be the most intense - and she wanted it to count. Undyne squirmed again, her hands grabbing onto the mattress in order to keep them in place, and Alphys smiled.

"Alphy..." Undyne suddenly croaked out. "Please touch me? _Please?"_

Alphys stayed quiet, using the cover of Undyne's voice to scoot closer, smiling mischievously. Even if she had said anything, Undyne wouldn't of been able to hear her, anyway.

Undyne then made a soft sound of frustration, her hands clenching onto the bed tighter. She desperately wanted Alphys to touch her, to kiss her, _anything_ , really, so long as she felt _something_ from her...

Alphys giggled softly, covering her mouth just in case, but decided she'd left Undyne for long enough. She very carefully crawled close to her, hoping she was light enough for Undyne not to notice.

She reached out, very slowly, and curved her hand around one of Undyne's breasts.

Undyne gasped, jerking in surprise, her eye flaring open beneath the blindfold in that shock. Alphys's hand was so warm, so soft, that it sent a peal of utter desire through her, so strong that she made another noise, akin to desperation, now.

Alphys blushed, but smiled, especially when Undyne reached up and grabbed hold of her wrist tight, holding her hand in place. Gently, still, Alphys trailed her fingers over her already-hard nipple, and Undyne's head fell back, another gasp leaving her.

It was _amazing_. To be able to feel, to _only_ feel, and not hear or see anything at all, made that feeling all the more intense - and powerful. Alphys had barely touched her, and already she was ablaze.

"Alphy!" she cried, her other hand scrabbling for her - but Alphys carefully made sure to stay out of range. "Alphy, please, keep touching me, you have _no idea!"_

Alphys giggled, knowing it was pointless to reply, as Undyne couldn't hear her at all. She moved away from Undyne's reaching hand, and with a growl, Undyne dropped it, looking frustrated.

She did, however, keep her hand upon Undyne's breast, mostly because she couldn't move it, as Undyne held it so tight it was impossible. She trailed her thumb over that hard nipple slowly, and Undyne purred deeply, relaxing a little and loosening her iron grip on Alphys's wrist, just a bit.

"Fuck," Undyne whispered, shifting a little and crossing her legs. "This is torture..."

Alphys wanted to remind her that it was actually _her_ idea in the first place, but obviously couldn't. Instead, she moved closer and leaned down, making sure Undyne couldn't tell what she was doing until the last possible second.

She just managed it. She flicked her tongue over Undyne's other nipple quickly, and Undyne yelped, jolting and sitting up, her hands reaching out to grab her. Alphys tried to move away with a giggle, but Undyne was too quick, and caught her by the shoulders with another cry - this time of triumph.

"Again!" Undyne pleaded, her nails digging into Alphys's shoulders, her head tilting back before she fell back again. Alphys gently prised her hands off and set them at her sides again, and Undyne growled and dug her fingers back into the bed.

Alphys waited quite a while, long enough that Undyne started to sweat, every sense she had left trained on sensing her wife and hoping she'd touch her - she didn't even care how, anymore, so long as she did.

Alphys then giggled, deciding that Undyne had had enough, and with a leap, she jumped atop Undyne and straddled her, leaning down and capturing that nipple between her lips once more, her tail wagging happily.

 _"Fuck!"_ Undyne cried, both shocked and relieved, and she reached up and grabbed Alphys so hard that Alphys laughed, a gesture Undyne could feel against her. "You sneaky little _minx!"_ Undyne added, growling. She arched up, grinding her hips against Alphys's, and to her delight, Alphys met it - and with added emphasis, making her lie back in bliss.

It was so hard to explain. Being deprived of sight and hearing made touch - and taste - all the more sensitive and powerful. When Alphys touched her, she felt it so much greater than it did normally, as though her wife was using magic on her - but she wasn't.

When Alphys kissed her lips, Undyne whimpered, wrapping her arms around her waist and pulling her down close, returning that kiss desperately and hoping it would never, ever end.

"Fuck me," Undyne begged, her voice small. "Alphy, please, _fuck me,_ I _need_ you, I _need you_ \--!"

Alphys was already reaching between them the moment she started talking, her hand touching them both for a moment to make sure they were close enough to connect. Undyne was still pleading when she shifted her hips down and rubbed close.

Undyne cried out Alphys's name, her voice breaking, and she shifted her hips up against Alphys's once more. Alphys kissed her again, and with a groan, Undyne grabbed her face and kissed back, just as Alphys started to move her body against hers.

Undyne was delirious almost immediately. Everything felt so much stronger, heightened, and every thrust of Alphys's hips against her own sent a jolt of such sweet pleasure into her that it was almost intoxicating.

Alphys watched her, making sure to keep her moves fast, loving how into it Undyne was, how much she wanted this - and Alphys, herself. Even blind and deaf, Undyne was eager for her, and there was nothing much else more arousing than that.

Well, perhaps one thing.

"Fuck, I'm close," Undyne gasped out against her lips, before kissing her again even harder, still holding her face.

Alphys moved faster, causing Undyne to moan again and cling to her even tighter, before she started losing control, her body going hot and her moves clumsy against her. She cried out - Alphys's name, more profanity, then pure nonsense - as she came. Alphys felt a jolt of pure lust hit her at the sight - and sound - of Undyne's orgasm, and she made sure to draw it out, especially knowing how sensitive and intense it would be for her.

And it was. Undyne felt that orgasm rip through her whole body, barely able to hear her own cries over how pleasurable it all was. It seemed to last forever, even, and she sobbed, burying her face into Alphys's neck, her hands now at her back and digging in.

When it gradually started to fade, Undyne sobbed again and collapsed, limp and boneless beneath Alphys. Gently, Alphys slid off of her, then reached up and started to remove the blindfold, then the earplugs.

Undyne's eye opened, the colour bright and blazing, her breaths short. She stared up at Alphys, who smiled at her and stroked her cheek gently.

"Fuck me, Alphy," Undyne gasped out.

Alphys laughed. "I-I already did," she teased.

Undyne grinned up at her tiredly, but her eye sparked.

"Alphy," she murmured.

"Mm?"

"Your turn."

Alphys didn't protest - and was rewarded immensely for it.


	15. Lapdance

**Notes for the Chapter:**

> I know I'm a few days behind, but I'll get there!!

It was random, but it was worth it.

Alphys was grading papers, grumbling quite a bit, when she suddenly found her chair pulled away from her desk. Before she could even ask, Undyne promptly sat down in her lap.

"Uhm," Alphys tried, but then Undyne did something that killed all speech from her brain.

Undyne grinned at her, then slowly moved herself down close. She placed her hands on the back of Alphys's chair and used it to slide herself down along Alphys's thighs, then back up again. Alphys swallowed, her hands still held in mid-air, her face turning bright red. 

But Undyne wasn't done. Oh not, not even close. She slid down to Alphys's knees, then turned herself around and sat back down, so that her back was to her wife. She arched back, pushing her rear right down against Alphys, who instinctively parted her legs without much thought or hesitation. 

Undyne licked her lips, glancing at Alphys over her shoulder, before she grabbed the edge of the desk and slid down again, before pushing back up and against Alphys - this time right between her legs.

By now, it was easy to feel, for both of them. Alphys could feel just how hot Undyne was - especially below - and Undyne could feel Alphys starting to warm up in exactly the same way. 

Undyne felt a jolt of excitement hit her at that, and she shifted, wiggling her rear a little right there and between Alphys's legs. Alphys gasped faintly, the gesture sending the most delightful friction through her, and she threw her pen to the floor and grabbed Undyne's hips hard. Undyne pushed back down in response, even harder, and Alphys uttered a cry, her eyes closing, leaning back.

Undyne glanced at her, her eye sparking, before she turned back around to face her. Alphys stared up at her, her own eyes blazing, and Undyne straddled her, continuing her slow, sliding dance upon her lap, her grin not once wavering.

"Undyne..." Alphys managed to squeak out, her hands back on her slip waist and digging her claws in. 

"Mmhm?" Undyne replied, not once pausing.

Undyne had an amazing body, lithe and slim, and when she used it, she used it well. Her backside was especially wonderful, as while it was modest, it was still firm and shapely - and felt wonderful rubbed against the right places. 

_"Fuck,"_ Alphys blurted out without control, starting to move in time with her wife. 

"Yes, please!" Undyne replied cheerfully, sliding slowly off of Alphys and to her feet. Before Alphys could even try to grab her back, Undyne picked her up and kissed her, carrying her right to the bedroom.

It didn't stop there. But it was an excellent start.


	16. Waxplay

"Alphy, I want to try this, and you don't have to do it, but fuck, I want to."

Alphys blinked up at her, surprised. She'd been playing a game, and had thought Undyne was grading papers, when suddenly Undyne appeared before her, holding her tablet and pointing at it, her face bright red and her eye bright.

"Uh," Alphys replied helpfully, but Undyne pointed at the tablet, so she looked.

Upon it was a simple-looking webpage, not at all graphic, but one that explained something called "waxplay".

Alphys, being who she was, already knew damn well what waxplay was, and she blushed redder than Undyne when she realised it. Undyne watched her eagerly, nodding when she saw that Alphys understood. 

"We have candles!" she added, her voice full of excitement. "Let's do it!"

"Uh, but your papers?" Alphys asked, shifting a little in her seat.

"Fuck 'em," Undyne replied, exactly the answer Alphys expected, really. "C'mon, get to the bedroom, I'll get the candles, get naked!"

Alphys laughed at that, as Undyne bounced in place as she said it. She saved her game, turned it off, and stood up, kissing Undyne with another giggle before turning to the bedroom. Undyne cheered and raced to the kitchen, which only made Alphys laugh harder.

When Undyne raced into the bedroom, Alphys was just finishing getting undressed. Undyne tossed the candles and lighter onto the bed, shoved the tablet onto the nightstand, and started throwing off her clothes, before she threw herself onto the bed and held the candles out to Alphys.

Alphys giggled and took them, kneeling down beside her as she got comfortable on her back, watching Alphys expectantly. "Start right here," she asked, pointing to her stomach. 

Alphys raised an eyebrow at her, then lit one of the candles, holding it to the side so that the flame caught the side and began to melt. "Won't that hurt?" she wondered, concerned. "Shouldn't we started on your arm or leg?"

"No!" Undyne answered. "I'm strong! I can take it!"

"You like the oddest things," Alphys observed affectionately, touching her cheek with her other hand gently. 

Undyne smiled up at her. "I'm just happy you're always so happy to try."

"I am one who always tries," Alphys agreed. 

Undyne was also one who always tried, Alphys realised affectionately. She had strange ideas about sex and pain, but Alphys was gradually coming to understand them. For Undyne, a warrior who had to fight through a great deal of pain to survive, it was no surprise that, if used in a safe environment, controlled pain could be stimulating. It was the rush of adrenaline and thrill of being hurt, but without the dangers - and a far better reward. 

Therefore, Alphys didn't mind testing these limits, so long as Undyne was always honest with her if she got close to overstepping them. And she always was. 

Therefore, Alphys slid her hand first over Undyne's stomach, tracing her fingers slowly over the smooth, slightly scarred belly. Undyne watched her, her eye glinting slightly with the candle's flame.

"Okay, ready?" Alphys then asked.

"Hell yeah," Undyne agreed. 

Alphys smiled at her enthusiasm, then very carefully tilted the candle, so that the gathered wax began to drip down and onto Undyne's exposed skin.

Undyne jumped and yelped in surprise - then laughed, tilting her head back and shifting a little. "Fuck!" she cried, sounding thrilled. "That's awesome!"

And it was. The shock of heat from the drops of wax barely lasted, almost immediately cooling into something warm and pleasant. As the wax hardened, it almost tickled. Undyne was immediately a fan.

"You sure?" Alphys asked softly, holding the candle up again.

"Yes! Alphy, do _not_ stop!" Undyne pleaded, looking up at her with red cheeks and a gleaming eye. 

Alphys smiled, kissed her briefly on her lips, then held the candle over her stomach again. Undyne lay back and relaxed, watching eagerly. 

Alphys was kind of starting to enjoy it. Undyne was not only sexy, but adorable. She poured a few more drops along the gentle curve of her stomach, careful to avoid any hair, and again Undyne jump - but this time with a purr. She closed her eye, one hand going up to her hair, her fingers sliding through it slowly. 

Alphys bit her lip; that was absolutely sexy to her. She moved the candle slowly upward, making sure the small drops followed, and she stopped just at Undyne's breastbone.

"Mm!" Undyne murmured, her eye fluttering and her body squirming a little. She arched up so that more wax hit her skin, and she shivered, licking her lips.

Alphys giggled, then paused, having a racy thought. She blushed. "Hey, uh, what-what about... your--?"

"Fuck yes!" Undyne cried, reaching up with her other hand and grabbing Alphys's wrist, starting her into spilling a bit of wax on the bed. "Yes, yes!"

"You don't even know what I was gonna say!" Alphys laughed.

Undyne looked up at her, her eye gleaming. "It better be breasts," she answered.

"Yes," Alphys agreed with another giggle.

"Do!" Undyne commanded with a wild grin, and Alphys laughed, her wife's expression so cute that she couldn't hold it in, even if she tried - and she didn't.

Alphys leaned down closer, smoothing her hand slowly over the soft curve of Undyne's left breast to start, gently teasing her clawtips over the nipple until Undyne sighed and relaxed, the nipple hardening delightfully under her touch. Again, Undyne's hand tangled into her hair, her eyes close and her teeth sunk into her bottom lip, and to Alphys's surprise, she was quivering a little - clearly in anticipation.

"The-the moment it hurts, tell me?" Alphys asked softly.

"The second," Undyne agreed breathlessly.

Alphys nodded, uncupped her hand from around the flame, and angled the candle again. Soon, the drips of wax (green, it should be noted) gently slipped from the end and made gentle splotches upon Undyne's skin, Alphys slowly circled the edges of her nipple to start.

And her reaction was incredible.

She moaned, arching back again, her other hand suddenly grabbing onto Alphys's hip and clutching tight. Her eyelid fluttered, and her face went bright red, her lips curving upward. Alphys was suddenly glad they always stocked soy candles, as they burned at the lowest heat.

"More," Undyne whispered, her voice strained, as though from far away. "All over..."

Alphys kissed her lips briefly again, something Undyne returned with another purr, and leaned down closer, dripping the wax very slowly just on the areola of Undyne's breast. Undyne hissed out, her nails digging into both her scalp and Alphys's hip, and when she took her next breath, it was with a small sound of longing. 

Alphys suddenly had an idea again. She dripped more, then used her clawtip to smear it up and upon Undyne's nipple to start, wanting to be careful.

She needn't of worried.

Undyne suddenly laughed, the sound mixed with a gasp, and she nodded, groaning from deep in her throat. "Th-that's _so good,_ Alphy," she murmured, arching back again. "You fingers... oh god..."

"More?" Alphys wondered gently.

"Yes!" Undyne begged. "Pour it right there, just let it hit!"

Alphys nodded, very slowly letting the green wax drip upon her erect nipple.

"Oh, _fuck!"_ Undyne cried. "Yes, yes, _yes!"_ She opened her eye halfway and added, "Touch me, please!"

Alphys smiled and moved her other hand down between Undyne's legs. Undyne immediately parted them, and Alphys slipped her fingers between those slick folds with a stab of delight, trailing them slowly along her clit.

Undyne growled, her eye rolling up. "The-the other, now, Alphy," she pleaded, her voice small.

Alphys shifted so that she leaned over more, then did the same as before: she dripped the wax in a slow circle over the areola, then smeared it upon the nipple before dripping more upon it. Undyne writhed, her breaths hoarse, now, her body flushing red all over. 

"Alphy..." she keened out. "Alphy...!"

"Yes, my love?" Alphys replied gently. 

_"Fuck me...?!"_ was Undyne's desperate response. 

Alphys shivered, the tone of Undyne's voice sending sharp arousal through her, and she blew the candle out and set it aside, then moved close and pressed against her wife, straddling her and propping herself up on her hands. When she did, she could feel the cooling wax upon Undyne's body, and the feeling was oddly sensual, sending another shiver through her: it was still warm, warmer, still, from Undyne's increased arousal.

Undyne immediately grabbed onto her, pulling her face down and kissing her hungrily, shifting her hips up and grinding them hard against Alphys's. Alphys made a soft sound, reaching between them for a moment, before she shifted down and rubbed her clit against Undyne's, the feel of the wax growing warmer beneath her own skin, now.

"Alphy," Undyne keened out against her lips, her hand slipping down and her arms wrapping around her, holding her so tight that Alphys was almost breathless. "Please, _fuck me,_ please, I need you...!"

Alphys buried her face into her neck and started to move, a quick but steady pace that had Undyne relaxing beneath her with a relieved and shaky laugh. Alphys slipped her hand up and gently cupped one of Undyne's breasts, using her fingers to loosen the wax and rub it upon Undyne's nipple. 

_"Alphy...!_ Undyne cried, her voice breaking and her body arching back, meeting each of Alphys's thrusts and urging her to go faster, feeling so hot and so turned on the edge that she could think of nothing else.

Alphys was certainly tumbling alongside her, and she complied, reaching for Undyne's hands and grabbing onto them, pinning them to the bed. She cried out, many times, already feeling close, and Undyne responded, on the edge, herself.

It was no surprise that Undyne came first, and she shouted it out, a mix of "fuck", "Alphy", and, of course, "nnngah!" She squirmed and writhed so much beneath her wife that said wife was having trouble keeping up with her, that was how intense her orgasm was. The thing was that Alphys was beyond caring; not long after Undyne was in her aftershocks, Alphys was thrown into her own storm, and she growled Undyne's name, her claws digging to her hands and her body practically gyrating above her. It was rare for them to come together so close to the same time, but it was wonderful - surreal, even - and both enjoyed every second of it.

When they both collapsed back onto the bed, they shared the same daze, gasping for breath and clinging to each other tightly, exchanging slow kisses and gentle touches.

When she could, Undyne whispered, "Alphy, that was _so fucking hot."_

Alphys giggled, her cheek resting on Undyne's shoulder. "Literally, I'm certain!"

"You have to try it. It's amazing."

"Undyne, you know I'm a wuss with pain," Alphys pointed out tiredly, her eyes closed. "Plus, I'm exhausted."

"Next time, then," Undyne promised, her own voice drowsy. "Next time."

She wasn't wrong, either.


	17. Massage

Alphys was not feeling well.

The winter had hit hard, and with it, hit those who were most susceptible to it first - and that certainly included Alphys. She was one of the first to get sick, and the first to need to take time off for it (sans filled in for her - with mixed results). And while Undyne prided herself in being able to take care of her wife when sick, this flu had hit Alphys so hard that there was very little she could do.

Alphys insisted that she was fine, and all she needed rest, but Undyne knew she was full of not just snot, but shit, too. So when Undyne came home to find Alphys still in bed, looking as though she barely moved from that same spot that Undyne had left her in the morning, Undyne had had enough.

She walked into the bedroom and knelt down on Alphys's side of the bed, reaching into her blanket nest to take her hot, sweaty hand. Alphys didn't react for a moment, until Undyne pulled her hand free and kissed it.

Then, she heard a soft moan, and Alphys whisper, "Wel-welcome h-home."

"Thank you, love," Undyne replied gently, kissing her hand again. "Can I see you?"

The blankets shifted, before Alphys popped her head out. She looked... terrible, to be honest. She was pale, squinting from lack of glasses and sore eyes, and her nose was running. She dropped her head back heavily onto the pillow and closed her eyes, shivering, and Undyne rubbed her hand gently.

"Hey," Undyne said softly. Alphys opened her eyes again slowly and smiled faintly, sending a wave of affection through Undyne. "Have you eaten, sweetie?"

Alphys looked away, then murmured, "Er..." 

Undyne sighed. "Do you think you can handle some soup?"

Alphys nodded shyly, hiding most of her face back under the blankets. Undyne smiled and kissed her forehead, then left.

She made the soup and brought it to Alphys, who was dozing by that time. Undyne gently woke her and helped her sit up, and Alphys looked up at her with gratitude. 

As she drank it, Undyne sat beside her and kept her company, telling her about her day, something Alphys listened to avidly and with happiness. She loved listening to Undyne, and this was no exception, sick or not. By the time she finished her soup, there was some colour back in her cheeks and light in her eyes. Undyne felt so much better, and she took the cup, set it aside, and kissed Alphys's cheek, rubbing the other.

"How are your muscles?" she asked softly. "Still stiff?"

Alphys looked down. "I... Undyne, it's okay. I'm j-just sick."

"Let me spoil you, dammit," Undyne replied cheerfully. "Are you sore?"

Alphys nodded slowly.

"Okay, so, lie down on your front over the blankets and let me give you a massage."

Alphys lit up and nodded, shakily doing so and relaxing with a hugh sigh. Undyne carefully sat down on Alphys's backside, making her giggle and squeak, before she leaned down and started.

Undyne, as mentioned, had amazing fingers. They were long and agile, and could find a kink in a muscle within seconds. She loved giving Alphys massages, as she knew Alphys benefited from them a great deal, since she wasn't as athletic and got stiff easily. It was even a greater pleasure to do this when Alphys was sick, as it made her feel better mentally and emotionally as well.

Alphys immediately relaxed, sighing again deeply and closing her eyes, burying her face into her arms and letting her senses be consumed by the feel of Undyne's hands.

Undyne focused on her shoulders, first, feeling the most stiffness, there, and gently eased the muscles loose, bringing an involuntary purr from Alphys. Undyne smiled faintly, loving those sounds, and she trailed her hands lower, before she paused.

"Alphy, take your shirt off, sweetie," Undyne advised gently.

Alphys did lazily, fumbling with it and tossing it aside without much care, before relaxing again. Undyne swallowed all of a sudden. The sight of Alphys's back send a jitter of warmth into her, one completely unexpected. She bit her lip and focused, trailing her fingertips down along Alphys's spine, relishing in the feel of soft, plump, and slightly-tough skin. Alphys had a beautiful back, shapely and strong-looking. To touch it was always a pleasure for Undyne.

Alphys loved being touched by Undyne this way. It was like putting all of her trust into Undyne's lovely fingers, and she never hesitated, knowing she'd be no safer. Each touch - especially now that she was topless - was exactly what she needed on her flu-stiffened muscles, and she already felt so much more relaxed.

When Undyne moved her hands to the small of her back, she couldn't bite back a soft moan of relief, her whole body flooding with pleasure. She smiled faintly, burying her face into the crook of her elbow, and her tail wagged a little.

Undyne, upon hearing this, when scarlet, her teeth sinking into her bottom lip and her whole body flashing hot - especially when Alphys started to wag her tail. Nothing made Undyne happier than giving Alphys pleasure, and hearing it was incredibly arousing. She shifted a little, trying to get a hold of herself, before she slid her hands to Alphys's hips, closing her eye and smiling at the feel of more soft, plump and generous curves. 

Alphys shifted, too, sighing again - only it was more of another soft moan than a sigh. She felt her own face heat up, especially when Undyne had tugged her pyjama bottoms down lower to get to her hips, and despite it all, despite her own state, she felt a flash of lust hit her. She felt immediately embarrassed, and buried her head even further.

Undyne didn't notice - she was getting too lost in the feel of her wife's body. Her hands moved up again, lingering on the small of Alphys's back, and to her delight, she heard another soft moan from her, though it was clear she was trying to hold it back. She opened her eye and looked down - and saw that Alphys was blushing, not just on her face, but all over.

She grinned; she knew exactly what that meant. 

She pulled her hands away for a moment, reaching up and pulling off her shirt, before she slid her whole body down and along Alphys's back. Alphys shivered, her hands digging into the mattress, and she kept her face hidden, even as Undyne hugged her close and pressed her breasts against her back.

"Alphy," she whispered, "I want you."

"I-I..." Alphys murmured, swallowing hard. "I-I want you, b-but, I d-don't want you to get sick..."

"If I was gonna get sick, I'd of gotten sick already," Undyne replied, tilting her head down and kissing the curve of Alphys's cheek. "If you're up to it, let's make love."

Alphys raised her head immediately, her eyes meeting Undyne's. When Undyne smiled, Alphys's eyes shone - and Undyne suddenly felt Alphys's tail wrap around one of her legs.

"Yes," Alphys whispered. "Your hands make me _crazy..."_

They kissed, and didn't leave the bed for the rest of the night.


	18. Masturbation

Alphys was so sure that Undyne wouldn't be home til late.

She didn't do it often, certainly not even close to how often she did when she was single, but sometimes, waiting for Undyne to come home was too long a wait - and she had needs she needed to take care of. (This was especially true if Undyne wasn't in the mood.)

So, when Undyne told her she had a staff meeting that was sudden and unplanned, Alphys was immensely disappointed. She'd had _plans_ for when they both got home, but now knew that Undyne would likely be too tired or frustrated when she got home to even think about sex, let alone want it.

Thus, when Alphys came home that evening, she went right to the bedroom, undressing quickly and grinning. She'd take care of it herself, and save her plans for another day, when they were both up to it.

Alphys had always enjoyed masturbating. From a young age, she discovered the pleasure to be found in her body, and while she had mixed feeling about how her body changed and looked the older she got, the ability to get off was never altered. She'd always been high-strung, always enjoyed a good orgasm, and had been used to providing her own for decades - until she and Undyne got together, that was.

But Undyne wasn't here, and only Alphys was. She lay down on her side of the bed on her back for a moment, relaxing and closing her eyes, allowing her hands to go over her own body, hesitating over the best spots: her neck, her breasts, her sides, between her legs...

Once her fingers touched there, she sighed, relaxing even more. Her mind was already on Undyne, and she smiled, the very image of her wife's face sending a fresh peal of lust into her. She leaned down a little and slipped her fingers deep inside herself, a soft moan escaping her as she imagined them to be Undyne's. She turned on her side, arching her fingers up and starting to move them, making sure they hit her soft spot each time, and she felt her face burn. 

She rolled over onto her stomach, arching down a little to reach deeper, her tail curling into a tight spiral as she felt growing waves of pleasure fill her. Her other hand dug into the mattress hard, her breaths going short, and she murmured out her wife's name in a strained voice.

Then, to her surprise, she heard the front door open, followed by, "Hey, Alphy! Guess what? I escaped! With food!"

Alphys jerked her hand away, breathless and shaking from both her actions and the lack of release, and she scrambled for her clothes, her face burning brighter but for completely different reasons, now. 

"Alphy?" Undyne called, her voice closer.

Alphys squeaked, about to grab her pants, when Undyne walked in. She turned, blushing all over, and Undyne blinked at her, her own face going red.

Then, Undyne slowly grinned, her eye going over Alphys's body slowly. 

"Did I interrupt?" she wondered, her tone teasing.

Alphys grabbed the closest blanket and buried herself under it, groaning in embarrassment. 

She felt Undyne sit down beside her, and she curled up tighter, still embarrassed. 

Then, Undyne said, her voice husky, "Can I watch?"

Alphys poked her head out in shock, wondering if she was still kidding with her, but Undyne was smiling shyly, completely serious. 

Alphys suddenly felt heat hit her again, and she swallowed hard. "I... I... y-yes?" she squeaked out.

"I did interrupt, after all," Undyne said softly, pulling the blanket down and uncovering Alphys slowly. "You should finish."

Alphys stared at her. "I-I should?"

Undyne licked her lips. "You should."

Alphys shivered, suddenly wanting to, very much. She was still shy, but she was also still horribly aroused, and she moved back onto the bed, staring up at Undyne for a moment, before she trailed her hand back down between her legs, her other moving up to her breast. 

Undyne's eye followed her hands, glinting, and Alphys couldn't look away from her. When Alphys slipped her fingers back up inside herself, Undyne swallowed hard, shifting a little. 

Suddenly, it was easy. Alphys turned on her side again, this time facing Undyne, her eyes still on her, and she arched her fingers up, returning to that pace she'd set for herself at once.

She sighed, her eyes suddenly fluttering closed, and her hand reached out and touched Undyne's knee, gripping onto it hard. She'd been on the brink when interrupted, and it was easy to get there, again - especially when the object of her arousal was right there with her.

"Undyne," she whispered, feeling close again, the name escaping her without control. She felt Undyne cover her hand and hold onto it, then felt her other hand touch her back. Alphys murmured nonsense at that, the feel of those hands only bringing her closer.

"Come for me," Undyne suddenly whispered.

"Oh...!" Alphys squeaked out, that voice cutting through it all. She cried out, moving her fingers harder and faster, and she started saying Undyne's name again - especially when her orgasm hit. She writhed, both against the bed and against Undyne's knee, and she flashed hot and felt that pleasure fill her, surrendering to it.

She then fell back, her hands falling to her sides, her eyes closed and her breaths quick and hard. She shivered, and suddenly Undyne hugged her close, warming her up immediately.

"Alphy," she whispered, "that was so _fucking hot..."_

Alphys shook her head. "N-no," she protested.

"Oh?" 

Alphys opened her eyes, then stared: Undyne was getting undressed, her eye mischievous and her grin hungry.

"Then watch me, and see if you understand why I think you're hot," Undyne concluded. She kicked her pants off and lay down on the bed, then met Alphys's gaze right on - before she started to slide her own hands over her own body, still grinning.

Alphys stared at her, her tail curling up again and her body flashing hot once more. She sat up on her knees, her hands clutching them tight as she watched. 

Undyne was enjoying this immensely, and it showed. She kneaded her own breasts for a moment, sighing, before she slid one of her hands down and parted her legs. Her fingers toyed with the curls there for a moment before diving beneath, pressing her fingers along her clit and slowly rubbing it between them. She never stopped looking at Alphys, and it soon grew easier and easier to relax, finding just looking at Alphys - naked, blushing from a recent orgasm, and watching her - a perfect cocktail for her own arousal.

Soon, she got lost in it, rubbing down harder and faster, gritting her teeth and shutting her eye, her breaths increasing. She suddenly felt Alphys cup her other breast, and she gasped out Alphys's name, something that earned her a gentle tease of fingers along her nipple. 

"Fuck," Undyne hissed out, her heels digging into the bed. "Fuck...!" She was already close, and she threw her head back, gasping, feeling her face burn but not caring a bit.

"Alphy...!" she keened out, just as those waves crashed into her. _"Alphy!"_ she cried again, not once, but over and over with each wave, her voice catching each time as she gasped for breath.

When she collapsed, grinning with her eye still close and her hands at her sides, Alphys leaned down and kissed her, right upon that grin. She returned it, and Alphys whispered, "You-you're right. That was hot. You're so sexy, Undyne."

And to prove it, Alphys suddenly leapt atop her, pressing her body against her and kissing her so hard that she groaned, grabbing hold of her tight and never letting go.

Dinner could definitely wait.


	19. Scent

**Notes for the Chapter:**

> This chapter is short and a little lacking mostly because this prompt gave me trouble and this was the best I could come up with.
> 
> Trust me: the length of the next prompt will more than make up for it.
> 
> CORRECTION: The chapter I'm referring to here will be the 30th, not the next one. Sorry!

Sometimes, Alphys noticed that Undyne's scent changed with her moods. As someone with a keen nose, Alphys had learnt very early how to use it to differentiate the most subtle of scents. This was especially useful in her work.

When she started hanging out with Undyne, one of the first things she became acclimatised to was her personal scent. Undyne didn't wear much artificial scent, opting for sweet-smelling body sprays (unless she had to work; then she didn't bother), subtle deodorants, and gentle-smelling shampoo. 

Therefore, it was easy for Alphys to be able to smell her own natural scent: a salty kind of smell, like gentle brine, and something uniquely sweet all on her own. She reminded Alphys of a kind of muffin, a healthy kind, almost earthy but with a hint of sugar to her. 

As they grew closer, and soon became intimate, Alphys was further pleased to discover that Undyne had far more scents to her than she could have ever imagined. Her sweat was sharp, sometimes unpleasant if after a workout, but oddly unique during sex. Her skin smelt saltier, true, but also strangely musky, a soft kind of musk that was almost sweet. 

And her intimate scent... Alphys could get drunk off of it. There was nothing like Undyne's intimate scent, nothing to truly compare it to, really, as it was all her own, and nothing in the world smelt like it but her. Alphys knew it well, and loved it very much. 

Undyne also smelt different, as mentioned, with her moods. When she was angry, she'd smell sharp and tense, even when she tried to hide it. When excited, she smelt sweeter. When tired, she smelt almost warm, like blankets full of personal scent. 

When aroused, Undyne smelt incredible. It was almost spicy, in the air, more hot than warm, and her skin radiated that need for sex, for release. She could never hide it, just like Alphys could never hide her heartrate from Undyne's keen hearing. 

Therefore, Alphys sometimes got warning in the form of Undyne's scent changing before she was pounced on. But that never stopped it from being just as fun and wonderful.


	20. Shower Sex

Undyne loved to shower. It was one of her favourite things in the world. The activity was practically made for her, after all, and every chance she had, she took it to shower. 

Alphys knew this. While she was also a fan, she certainly wasn't as enthusiastic as Undyne when it came to the length - and frequency - of a shower. She liked them enough, but certainly not as much as her wife.

One evening, after a horribly balmy and humid day, Undyne had gone directly to the bathroom and into the shower stall, stripping on the way, before immersing herself in cold water at once. She had been so overheated, and was starting to feel dry, and needed this soak very much.

What she had forgotten was that Alphys didn't take too well to the heat, either. Though she'd lived there for years, Alphys had never gotten used to Hotland and its constant, unrelenting heat. She'd thought, once on the surface, she'd be spared that heat forever. That day had proven her incredibly wrong.

She was desperate for a shower, too. So, meekly, she knocked on the door and called Undyne's name.

"Yeah," Undyne replied, sounding distracted.

"Can... can I join you?" Alphys wondered. "I'm... melting..."

Undyne laughed, then opened the door to the stall. Alphys raced into the bathroom and into the stall, already naked, as she'd hoped for this (and, if she'd failed, she'd remain naked and melt on the kitchen floor). 

Undyne grinned at her and pulled her in, then shut the door behind her. It was a snug fit, but they could still move around well, and soon, they were both standing under the cold relief of the shower, just hugging and sighing, feeling their burning skin cool off at last. 

Alphys rather liked this. It was intimate, and comforting. She moved closer to Undyne, burying her face into her chest and sighing deeply. Undyne chuckled and kissed the top of her head, hugging her tighter, and Alphys sighed deeply.

"This is nice," Alphys admitted softly, her voice echoing a little.

"Mm," Undyne agreed, leaning down and gathering her closer, so that the water hit them both nicely, but not in their faces. Alphys closed her eyes, her whole body relaxing and feeling better. Undyne nuzzled her, feeling the same - better, even, as having Alphys in her arms was a wonderful, added bonus. 

"I feel more solid, now," Alphys murmured softly, keeping her face right between Undyne's breasts with her eyes closed, smiling. Her arms were around her wife's slim waist, and her hands were flat against the small of her back. Undyne kept her own arms around Alphys's shoulders, one hand stroking the back of her head slowly, her other hand lazily drawing invisible circles upon her shoulder.

"Mm," Undyne repeated, grinning and feeling embraced by pure bliss. "I do prefer a solid wife," she admitted gently, her voice a soft whisper.

"Undyne," Alphys whispered, "I love you. I love moments like these, when we're just still, and in our own little bubble, in our own universe."

Undyne opened her eye, a stab of affection hitting her heart so sharply that she bit her lip. "Oh, Alphy," she murmured. "I absolutely agree."

"I wish I could spend forever with you, here." Alphys continued, her voice so soft and full of affection that Undyne held her closer. "I love you so much, Undyne. So much..."

Undyne reached down and touched Alphys's chin, raising her head up so that they could look at each other. Undyne's expression took Alphys's breath away. It was so open and full of such clear love that Alphys was spellbound, her eyes widening. 

"Undyne," she whispered, reaching up and touching her cheek, curving her hand around it. Undyne's eye closed and she leaned into her palm, biting her lip this time, her face falling to one of need.

"Alphy, I love you, too," Undyne replied, her voice wavering. "I love you so dearly that... that... fuck, I'm shit at words and wish I knew how to explain it better..."

Alphys smiled at her, so kindly that Undyne swallowed hard. "Then don't use words, my love," she suggested, her eyes glowing.

Undyne swallowed again, another wave of love filling her, this one coupled with desire, and without another word, she leaned down and kissed Alphys, holding her face between her hands and putting everything she could into it. Alphys raised up on her toes and kissed back, her arms holding her tighter, and they both made a soft sound, then, the combination of the cold, soothing water and their increasing heat of desire almost intoxicating. 

"Alphy?" Undyne murmured, her hands reaching down between them to cup around Alphys's breasts. When Alphys nodded, moving her head down to kiss the curve of Undyne's neck, Undyne whispered, "I want you."

"I _need_ you," Alphys replied right away between kisses and nibbles, her own hands trailing down and lightly brushing along Undyne's gills, on both sides. Undyne shivered and leaned back, her eye closing, a soft moan escaping her, and Alphys smiled, loving that sound.

"Alphy..." Undyne gasped out, her hands freezing upon Alphys's breasts, the peals of sharp pleasure from those fingers stroking her gills sending her into a daze. She stepped back, leaning against the wall of the stall, and Alphys followed, pressing her slick body along hers, still standing on the tips of her toes. 

She dipped her head down and cupped one of Undyne's breasts, the nipple already erect, and licked along it slowly, teasing it and capturing it between her lips, all while her other hand still worked her gills. Undyne grabbed her hips, digging her fingers in hard. She made a soft sound from deep in her throat, her head tilted back and her eye shut, and Alphys's tail wagged, a shiver of happiness going through her. 

"Alphy...!" Undyne repeated, her voice holding an edge to it. Alphys smiled, moving to kneel in front of her, but Undyne grabbed her and stopped her. She had seconds to look up - and found Undyne staring at her hungrily, her eye blazing and her wet hair curling around her face. Undyne then grabbed hold of her and lifted her up, pulling her legs up so that they were firmly around Undyne's waist. Alphys clung to her with a surprised gasp, before her mouth was covered by Undyne's and she was pushed against the opposite wall, Undyne pressing against her hard.

Alphys gasped, a sound Undyne kissed away, as the way Undyne rubbed against her brought a delightful jab from between her legs. Undyne shifted, kissing her harder, her tongue slipping against her own, and she reached down and grabbed one of Alphys's legs, moving it from her hip to between her own, before she hiked up her own leg, propped her foot upon the ledge, and pulled Alphys close, so that she straddled it. Alphys's legs tightened around it immediately, and she moaned again, feeling that wonderful, firm and slick muscle rub against her vulva close. 

"Alphy," Undyne gasped against her lips, her arms going around her neck, her breasts rubbing against Alphys's and her hips grinding close. _"Alphy, fuck me..."_ She pleaded it, and Alphys reached up and tangled her hands into her soaked hair, nodding and kissing her again. She started to move against her, rubbing down against her thigh hard, and Undyne's eye rolled up, shifting and doing the same with Alphys's with a barely-suppressed cry. 

The heat of their bodies was immediately cooled by the chill of the water as they moved, their rhythm slow and lingering to start, both enjoying the conflicting sensations and wanting more and more the longer they went. 

This became even more clear the moment Undyne growled, reached for Alphys's hands, and yanked them down from her hair and back to her gills. Alphys stroked them the second her fingertips landed, and Undyne buried her face into her neck, grinding against her harder and urging her to go faster.

Alphys leaned her head back against the tiles, her eyes closed and her breaths short, a smile on her face as she gripped Undyne's leg hard - and feeling even more enjoyment when she felt Undyne do the exact same. Undyne's hands went to the wall, then, using it for leverage to go harder, and Alphys gasped in delight, her tail hooking around Undyne's shin tight. 

"Fuck, you're so _good,_ Alphy..." Undyne keened out between gasps, her eye shut tight and her face bright red. "Oh, god, I can't ever get enough of you..."

Alphys shivered, the words meaning so much to her. "Undyne," she murmured, her voice strained and catching with each thrust of their bodies. "Oh, Undyne... I'll never leave you... you never have to worry..."

Undyne's head jerked up, her eye open and wide and her mouth open in shock. Alphys looked back at her, her eyes dark but serious, her smile so gentle. Undyne uttered a small cry, her heart aching with love, for that was exactly it, exactly what she was afraid of. 

"Alphy," she gasped out, her voice choked and her eye stinging. "Alphy, keep fucking me..." It was all she could think of to say, all she could think of saying. "Fuck me, make me yours, make me yours _forever..."_

"As long as _you_ keep fucking _me,"_ Alphys answered breathlessly, her voice already slurring and her eyes fluttering closed. "Don't stop, don't stop, _don't stop...!"_

"Never," Undyne growled, pushing her harder against the wall and moving both faster and harder, bringing a sweet- sounding moan from Alphys, pure music to her ears. "Not until you come for me," she added, pleading it. She wanted Alphys to come, and come hard, and feel that pleasure that she so greatly deserved to feel. 

"Yes...!" Alphys cried, clinging to her and burying her face into Undyne's chest, her voice breaking. Her body became clumsy, her moves jerky, and soon she started to cry out, those special cries that only Undyne truly knew, as she was the only one who could bring them from her. _"Undyne...! Undyne!!_ she cried, and her orgasm hit, so hard that she cried out more than once and stumbled, her claws moving to Undyne's hips and digging in hard. Undyne held her close, moving with her to make it last, and Alphys cried out again, her whole body hot and flashing red.

When she calmed - and it took some time - she relaxed against Undyne for a moment, gasping for breath and shaking. Undyne kissed her all over her face, holding it up between her hands and rubbing her thumbs over her burning cheeks, making sure the water hit her just right to cool her off. 

Then, Alphys whispered, "Undyne, keep fucking me, until you come."

Undyne jolted, the words sending a rekindling of lust into her, and she grinned, especially when Alphys opened her eyes and grinning back, shifting her body so that her thigh rubbed hard against Undyne's vulva this time. That was all it took, and Undyne pinned her against the wall again and started moving, hard and fast. 

Alphys purred, her eyes closing as she felt aftershocks hit her with each of Undyne's thrusts, and the sound made Undyne moan and hold onto her tight, burying her face back into her neck.

Alphys then started stroking her gills again, moving her fingers in time with each shift of Undyne's hips, and Undyne threw her head back and cried out, her voice breaking. She tried to speak, to tell Alphys how good she was, how amazing she felt, and how close she was, but all she could get out was, "Alphy, oh god, _fuck, fuck!!"_

Alphys, however, understood her, regardless, and encouraged her to move faster, leaning down and whispering into her ear, "Come hard, feel that rush, and get high alongside me..."

"Oh, Alphy...!" Undyne pleaded out between her teeth, and after that, it took only a few more thrusts before she came, her orgasm crashing into her so hard that she sobbed, clutching Alphys to her and staggering, barely able to stay on her feet from the force of it. Alphys held her close - and on her feet - as she was overcome, kissing her gently and making sure to draw it out, her fingertips lingering over her gills. 

Then, Undyne collapsed against her, gasping so hard for breath that each gasp was vocal. All she knew, all she could feel, was Alphys, and it was the best feeling in the world. She laughed suddenly, the sound hoarse, but still genuine, and Alphys giggled in reply, holding her close. 

They stayed like that for a moment, catching their breaths and calming down, their pleasure truly like a high, just like Alphys said. It was so common between them, it was almost like a drug; they were addicted not just to that feeling, but to each other. 

After a moment, Undyne reached up clumsily and moved the showerhead, so that the water poured over them better, and they both sighed. They were certainly in need of cold, now, feeling almost feverish in their post-coital haze. 

Then, Alphys whispered, "Undyne, I love you. If we weren't already, I'd ask you to marry me all over again."

Undyne smiled at her, and Alphys looked up at her, her face pink and her eyes dark. "The sex is that good, huh?" Undyne teased.

Alphys frowned, looking sincerely worried for a moment that Undyne was being serious - until Undyne laughed and nuzzled her cheek with her own. Then she relaxed and laughed, too, clinging closer onto her.

"It's you," she answered, anyway, just to be clear. "Undyne, it's always you. It always has been."

"As it has been with you for me, Alphy," Undyne replied.

They kissed, and remained under the downpour for just a bit longer - just because.


	21. Scars

**Notes for the Chapter:**

> This one is less about sex and more about emotion. It's pretty sad, but it's also important.

Neither Alphys nor Undyne were strangers to scars. This was something they both knew about each other, even as friends, but as wives, they could finally observe it upfront and discuss it frankly, in a way that they never could as friends - and with painful results.

They'd just finished making love, and were cuddled close, catching their breaths and sharing a satisfied smile, eyes closed and bodies hot. 

Alphys's eyes were closed when she suddenly felt Undyne shift closer and rest her head on her chest. She reached over and took hold of Alphys's left arm, pulling it over, before she started to slowly trace the thick lines upon the inside of her wrist.

Alphys shivered, then murmured, "Wh-what are you doing?"

Undyne was quiet, her eye on her arm and her teeth sinking into her bottom lip. Tracing those scars - ones visible only if you looked closely, due to Alphys's thick, tough skin - made her feel deeply sad, as she knew exactly where they came from and why. 

"Undyne..." Alphys said, her voice gentle. She opened her eyes and looked down at her, and saw that her eye was wavering, close to tears. "It-it's okay, love."

"No," Undyne answered, her voice small. She pulled her arm to her lips and trailed them along those lines, her eye closing and her tears falling free. "It's not fucking okay, Alphys."

"Undyne--,"

Undyne shook her head, kissing them again slowly, starting to shake a little. She was imagining it, and it was painful. She couldn't imagine being in that much pain, and knowing Alphys had been - and more than once - hurt her deeply. 

"It's okay," Alphys insisted, using her other hand to stroke Undyne's slightly-sweaty hair gently. "It is now, anyway."

"I'm sorry," Undyne murmured, her voice breaking, resting her cheek against Alphys's arm. "I'm sorry I wasn't there. I'm so sorry..."

"Undyne, it happened before we met," Alphys explained, touching her other cheek gently. "The first time, anyway..."

Undyne's head jerked up, shocked. She stared at her wife, and suddenly Alphys regretted what she said.

"What are you saying?" Undyne demanded, sitting up and pulling away from her. 

Alphys looked away, wishing she could disappear. "The-the other times... I... I knew you... we were friends..."

"Why didn't you tell me?!" Undyne cried, her voice breaking again.

"I didn't... I didn't want to bother you..." Alphys admitted, covering her face with her hands and curling up a little. "I didn't want... I didn't want t-to burden you.."

Alphys felt herself start to cry, and suddenly, Undyne leaned down and grabbed her into a tight, breath-stealing hug. Alphys's eyes opened in surprise, returning it, but then she felt Undyne trembling, and she realised she was in tears, too.

"Alphy," she sobbed, "no! You're never a burden, ever! Never then, and never now!"

Alphys swallowed back a protest, closing her eyes and burying her face into Undyne's shoulder, tears of her own escaping her. "I'm-I'm sorry," she whispered. "I just didn't want to hurt you..."

"If you'd succeeded," Undyne answered, "if you'd... gone... Alphy... oh god, I would have... I would have followed you..."

"No!" Alphys cried, reaching up and pushing her away, shocking her. They both sat up, and Alphys glared at her through her tears. "No, Undyne! You can't do that!"

"Alphys, I've been in love with you since the moment I met you!" Undyne blurted out, grabbing her face in her hands, using her thumbs to brush away her tears. "Since we've been friends, I've loved you! I've-I've never been able to imagine a life without you!" 

She paused, closing her eye and sobbing, and Alphys flinched, reaching up and placing her hands on Undyne's forearms. 

"Undyne," Alphys whispered fearfully. "Stop."

"No!" Undyne snapped, her eye open and blazing, her teeth bared. "Dammit! Alphys, I know you hate yourself, and I know you hurt yourself sometimes because you can't cope, but if you... k-killed yourself... if you... d-died..." 

Undyne's voice choked, and she lowered her head, her hands dropping to her sides as she dissolved into tears - the likes of which Alphys had never, ever heard from her before. They were gut-wrenching, physical, ripping from her throat and chest and shaking her whole body with their violence, her voice keening with her pain.

Because it was true. 

All of it. 

The very idea of Alphys being out of her life, for whatever reason, threatened to break her heart. The very idea of Alphys killing herself made it even worse - it made her feel on the brink of insanity.

When Alphys had confessed to her that she'd cut her wrists one time and tried to bleed out in the bowels of the True Lab (though she'd lied and said it was in the bathroom) - only to pass out and be found by Mettaton, who brought her to the hospital just in enough time to save her - Undyne had cried so hard she had thrown up, so heartbroken that it terrified Alphys. She'd made Alphys promise to never try again, to come to her first - but Alphys broke that promise.

And it threatened to break Undyne's heart. 

She knew scars, knew what it was like to have your skin ripped and torn and made to bleed for what seemed like forever, but those wounds were from training and skirmishes amongst her fellow monsters, and she'd never been cut deep enough to be in danger - though she'd certainly needed stitches several times. 

This was so different. 

It was like night and day, ceiling crystals and real stars.

Undyne collapsed in front of her, her hands clutching at Alphys's legs and her nails digging in hard, her sobs shaking even them. Alphys stared at her, bewildered and in shock and pain. She leaned over and rested her head upon her wife's, wrapping her arms around her shoulders, rubbing her back slowly, unable to keep her own tears at bay.

"Alphy..." Undyne sobbed out. "Please don't leave me..."

Alphys jumped in surprise, then leaned closer and shook her head. "Never, Undyne," she promised.

"No," Undyne snapped. "I mean, please don't ever kill yourself."

"I know, Undyne," Alphys whispered, kissing her back gently. "And I won't."

"How can I be sure of that?!" Undyne demanded, her voice muffled but broken. "You tried it when we were friends, and never told me!"

"Undyne..." Alphys bit her lip, hesitating. It was true, and she hated lying, but when she'd promised, she'd truly tried to uphold it for Undyne's sake. It was only when she'd run out of ideas to help the amalgamates that she'd lost her control, and tried again. She hadn't been able to tell Undyne, because Undyne didn't know about her mistakes, yet. Therefore, she vowed to go quietly, to spare Undyne as much pain as possible.

Clearly, she'd been a fool.

"I never told you, because I'd never told you about the-the experiments," she confessed, her voice small. "So I d-didn't know how..."

"I wish you'd told me about that, too!" Undyne cried, slamming a fist onto the bed in her frustration. "Why, Alphy? Why did you keep so much from me, when I could've helped you?!"

Alphys sat up and covered her face with her hands, bursting into tears. "I don't know!" she answered, her voice breaking. "I don't know, I don't know! It j-just hurt so much, and I just wanted it to stop, and I didn't want to hurt you, too! I didn't know, Undyne! I didn't know anyone cared about me at all, let alone you!"

Undyne raised her head in the middle of this, surprised, and she sat up, reaching forward and placing her shaking hands upon Alphys's knees. She was still weeping, but Alphys's tears, to her, were far more important.

"I never meant to hurt you!" Alphys sobbed. "I truly thought I was making sure I wouldn't! I didn't know, Undyne! How could I?!"

Undyne moved closer, biting her lip, and gently took hold of her, pulling her close. Alphys grabbed onto her tight, her tears pouring from her in such a painful way that Undyne started up again, too. 

"I..." Undyne whispered. "I should have told you I loved you the moment I knew for sure."

Alphys sobbed out her name, digging her claws into her back, and Undyne rested her cheek atop her head, rubbing her back slowly. 

Scars weren't news to either of them. But their histories... those they were still learning. And sometimes, history was more painful than the wounds had been before they were scars.


	22. Against a Wall

One time, Alphys tried to get Undyne against the wall - with partial success.

It was always Undyne who pinned Alphys, and Undyne who always had her way with Alphys. This time, Alphys wanted to be the one pinning, and not the one pinned.

So, when she caught Undyne walking to the kitchen for some water, she raced to her feet, grabbed her, and kissed her lips hard, pulling her down and holding her face in her hands. Undyne squeaked in surprise, stumbling with her arms flailing for balance for a moment, before she managed to grab hold of Alphys return it - with sudden and increasing interest, too.

Alphys was thrilled by this, and immediately started pushing her backwards towards the closest wall - the one in the hallway between the kitchen and living room. The moment she managed to slam Undyne against it, Undyne grunted and grabbed hold of her tighter, feeling sudden and urgent need fill her - turned on especially by Alphys's firmness. 

Alphys then tried to push her up, her hands fumbling for the back of Undyne's knees, having to stand on her toes to even attempt it. She stumbled out of the kiss in her haste, and Undyne lunged down to try and grab her back, reaching down and pulling her off of her feet to do so - exactly the opposite of what Alphys was aiming for.

"Wait," Alphys gasped out between kisses. "I want to... I want to have you...!"

But the more she tried, the more she began to understand that she was simply too short to attempt this - at least when it came to having actual sex. 

However, she had one more idea that was almost as good, and with a grin, she pulled away, jumped down to her feet, and took hold of Undyne's waist again. Undyne tried to grab her and flip them around, but Alphys shook her head and held firm, and Undyne squirmed, looking at her with longing.

"Alphy," she tried to begin, but Alphys silenced her with a simple action: she took off Undyne's pants and underwear in one go, sliding them down to the floor. 

Then, she grabbed Undyne's hips again, knelt down, and brought Undyne close, hooking her legs upon her shoulders. Undyne stumbled and grabbed her head, her heels digging into her back, and Alphys stumbled a bit herself, having to adjust a little to gain her balance back and a proper hold of her wife. 

Alphys grinned up at her from between her legs, something Undyne swallowed at hard with a bright red face, before she leaned down and buried her face between Undyne's legs, pressing close and - finally, at last - pinning Undyne to that wall. 

Undyne arched against that wall and groaned the moment Alphys's lips touched her folds, and she gasped when Alphys started licking slowly. She looked up, just as Undyne reached up and pulled her shirt off, tossing it over Alphys's head, before grabbing hold of her head again and grinding against her, crying out breathlessly.

Alphys finally understood why Undyne loved doing this to her. While it wasn't quite the same, it was still absolutely thrilling, and Undyne was practically malleable in her hands, lost to her tongue and loving every second of it.

"Alphy," Undyne gasped out again, starting to move jerkily against her, and Alphys grinned and dove deeper, digging her claws into her hips. Undyne groaned, arching back again and urging her to go faster, and Alphys happily complied, her tail thumping against the floor.

 _"Alphy...!"_ Undyne shouted out then, surprising Alphys, she arched forward and cried out, the sound ripping from her throat, and she came, hard, so hard that she nearly had them both tumbling to the floor, Alphys having to struggle to keep her up.

Undyne gasped, still holding Alphys close, trembling, and Alphys slowly pulled her head away, looking up and licking her lips, before smiling happily. Undyne stirred, her eye opening halfway, and she smiled back lazily, blinking slowly. 

"Fuck, that was so good," she whispered, her voice hoarse, now. 

Alphys wagged harder, wiggling a little in her glee. "Really?"

"Yes," Undyne agreed, leaning down and resting her forehead to hers, her eye closing again. 

"I finally got you against the wall," Alphys added, unable to resist.

"Mmhm," Undyne agreed, kissing her nose a few times, still wearing that lazy smile.

Gently, Alphys moved away and helped her down, and Undyne leaned on her for a moment, still trembling from release. 

Then, Undyne reached down and grabbed Alphys's rear. 

_"We're not done, Alphy,"_ she growled, sending shivers through Alphys and igniting her al over again.

This time, Alphys was against the wall, the pinned one once more. But this time, she didn't mind - not even close.


	23. Sixty-Nine

It was one of the very first things they tried together.

Before they were married - before they even had their place on the surface - they spent much of their time at Alphys's place when they could, thrilled that they were finally together at last and wanting to make up for time lost.

That first kiss on the beach had sparked a fire between them, one that had yet to be banked weeks later, and the moments they could, they explored each other, both body and mind, finding the other unable to resist.

That afternoon, they were already making out on Alphys's bed and naked, fully intent on each other. They hadn't had sex yet - neither were quite ready, yet - but moments like these made that moment grow closer and closer.

When Undyne reached down between them, however, Alphys stopped her, breathless. Undyne blinked and looked up, and Alphys stared at her, her eyes blazing and her face scarlet.

"Undyne," she murmured. "You-you can say no, but, do you think we could, uhm... we could try... uhm... six... sixty-nine?"

Undyne's eye widened and she grinned, nodding and pulling her hand back. "Yes, please!" she agreed.

Alphys smiled back, feeling butterflies assault her belly in the best way, and she moved away and sat up, for a moment nervous. "Uh-uhm," she murmured, as Undyne sat up, too. "So-so, how--?"

Undyne grinned and tackled her, then pulled her close and flipped her over, so that Alphys was atop her. Alphys kissed her, unable to resist, and for a moment, once again, they were making out, delighting in the feel of that simple action, alone.

Then, Undyne whispered, "Flip around, Alphy."

Alphys blushed, a little shy, as she suddenly imagine just how much Undyne would see the moment she did that. However, she also trusted Undyne, especially at this point of their relationship, so with a burning face, she shifted, then flipped around, holding her tail up and curling it to keep it out of Undyne's face - while other parts were not. Undyne grinned and made a purring sound, just as Alphys got comfortable, propping herself on her hands and keeping her balance that way, spreading her legs and placing her feet on either side of Undyne's head.

She looked down, and smiled; Undyne was so close to her, now, so easily accessible, that she shivered and licked her lips, leaning down immediately and licking along Undyne's soft slit slowly.

Undyne growled, her eye closing, before she wrapped her arms around Alphys's waist and pulled her down to her face, burying herself between her legs and snaking her tongue out between her folds, licking slowly and closely. Alphys jumped, gasping a little against Undyne's own folds, before she could continue.

Alphys was suddenly very aware that this was going to be distracting. Undyne had a wonderful tongue, if a bit short, and when she moved it up to her clit, Alphys cried out again, her own tongue freezing with that jolt of pleasure. Her claws dug into the bed, and her hips moved down and with Undyne's actions, her breaths going short.

Undyne raised an eyebrow, easily noticing this change in her girlfriend, and she decided to take full advantage of it. She reached up with one hand, her tongue still fixed on Alphys's clit, and brought two fingers between those slick folds, reaching deeply and curving them up.

"Ah!" Alphys cried, jolting again and arching her head back for a moment, her eyes closed tight. "Oh god, Undyne, that's _incredible!"_

Undyne was thrilled to hear this, and didn't stop. Alphys gasped for a moment, her body flashing hot, before she suddenly growled, herself, burying her face between Undyne's legs closer and flicking her tongue along Undyne's clit, hard and fast and lingering, her heart racing with eagerness to both please and be pleased. She lowered down and grabbed Undyne's hips, and Undyne grunted, the feel of that sending a spark of lust into her - especially coupled with the feel of Alphys's tongue.

"Alphy," Undyne murmured, her voice muffled. She arched her hips up and moaned softly, her fingers increasing as her own pleasure did.

"Mm!" Alphys answered, gasping with each breath, her body getting hotter and hotter the closer she got. "Mm! Mm-Undyyyyne...!" She threw her head back, her voice catching, and suddenly she couldn't think anymore, could barely breath, not even Undyne's name, though she desperately tried to.

Undyne grinned, understanding exactly what that meant, and she pumped her fingers harder and faster, her tongue flicking over Alphys's swollen clit quicker.

Alphys cried out again, then again, before she stumbled and keened out, her claws digging into Undyne's thighs hard as she came. Undyne slowed down, but didn't stop, and Alphys collapsed, panting and almost blacking out, her body red and sweaty.

"Good?" Undyne wondered gently, pulling her hand and mouth back slowly.

"Undyne, oh-oh m-my god..." Alphys moaned, resting her face on the back of her own hand for a moment. Then, her eyes opened, and she leaned back down, starting to lick Undyne's clit again right away, holding her hips again tight.

Undyne leaned back and groaned, her eye closing tight and her body moving alongside her tongue. Alphys squirmed, her tail uncurling and wagging happily, eager to make Undyne come, now.

And it didn't take long, not with how fast and hard Alphys's tongue worked over her. Undyne cried out, then arched back, crying out nonsense and digging her nails into Alphys's rear, surprising her into giggling a little as she slowed down.

"Alphy...!" Undyne purred between gasps, before laughing softly and rubbing Alphys's backside slowly, bringing another giggle from her. "Fuck, that was hot. C'mere?"

Alphys looked over her shoulder, beaming, before she turned around and grabbed her into a hug, kissing her cheeks so many times that Undyne started squirming and laughing, holding her close.

"That was amazing," Alphys concluded, nuzzling Undyne's cheek with her own. "I loved it. I..." She blushed, turning and hiding her face in the pillow closest to her. "I love you, Undyne..."

Undyne closed her eye and bit her lip, a smile curving her lips, and she held Alphys closer, kissing her. "Alphy," she whispered, "I love you, too, sweetie."

Alphys squeaked, digging her claws into Undyne's shoulders, before she raised her head and kissed Undyne's lips, her face red and her eyes full of tears. "I love you," she whispered between kisses, holding her face between her hands. "I love you, Undyne... I love you..."

"I love you," she whispered back each time, meaning it more and more with each recitation.

And that love would only grow.


	24. Smiles/Laughter

One of the first things that Undyne fell in love with was the fact that Alphys could always make her laugh.

Even when they were just friends, when they barely knew each other, Alphys could always make her laugh - even when she felt as though she could never laugh again.

The most important moment that cemented this love was when Undyne came over one afternoon to hang out, and she was in one of the foulest moods she'd even been in. But she'd promised Alphys she'd hang out and, damn it, she never broke her promises.

Alphys's face fell the moment she saw Undyne's, and she dropped the cups of ramen on her desk and said, "Wh-what's wrong?"

Undyne closed her eye, then growled out, "It's work."

She felt Alphys touch her hand. "Okay," she replied gently.

Undyne lowered her head. "Some shit happened, a fuck-up with some of the weapons storage, and I got into big shit. I wasn't even on duty. I wasn't even _there!_ But the fucking hammer came down on me, as usual, because of course it would, I'm the crazy one, so of course it's my fucking fault!"

She was shouting, now. She knew it. She tried to pull back, but couldn't; she was too angry.

But she'd forgotten her audience, and when she looked up, Alphys's head was lowered, her hands tangled in front of her, and she was shaking a little. Undyne had forgotten that shouting scared Alphys - well, angry shouting - and had just done it without even thinking about it.

She opened her mouth, about to hurriedly apologise, to admit that she was such an asshole, but then, to her surprise, Alphys murmured the single sentence she'd never forget.

"They already think you're so powerful, to trash weapons you didn't even touch."

Undyne stared at her, feeling her face suddenly break into a smile. Then, she laughed, the sound startling them both, and Alphys looked up.

"Yeah!" Undyne suddenly agreed. "Damn right! You're right, nerd!"

Alphys smiled, lighting up, and Undyne never forgot that, either.

Alphys never stopped making her laugh - especially the closer they got. When they started dating, and becoming intimate, that laughter never ended, even at the silliest times.

* * *

"Oh, god, oh god," Undyne was saying, over and over again. Alphys listened, both nervous and excited, as she had no clue what she was doing and fully trusted Undyne to help her.

And she was. "Keep going, keep going, don't stop! _Don't stop! Ah!! Alphy!!"_ She felt Undyne dig her nails into the back of her hand, just as her body started losing control. "Alphy, I'm coming! Oh god, don't _fucking stop!!"_

Alphys certainly did not, and was rewarded by both Undyne crying out - the loudest she'd ever heard - and by the sudden change in taste and increase in warmth and wetness.

Alphys pulled away slowly after a moment, just as Undyne fell back, gasping for breath, her hands dropping limply at her sides. Alphys raised her head and grinned, her tail wagging happily, and she was then startled.

Undyne started laughing. A lot.

It started soft, true. But it didn't take long before it suddenly grew into an all-out, full-bodied belly laugh. Undyne curled up on her side and laughed, looking so overjoyed that it shocked Alphys into momentary paralysis.

"E-er," she managed to get out, but then she found herself grabbed and pulled down to the bed, Undyne pouncing on her and hugging her tight as she laughed. Alphys smiled, then couldn't help but join in, always thrilled whenever Undyne was, it was true.

When Undyne finally calmed, leaning heavily on Alphys and brushing the tears from her eye, Alphys looked up at her shyly and asked, "Wh-what was so funny?"

Undyne grinned at her. "You. You were."

Alphys blushed, taking this the wrong way. "It-it was bad?" she squeaked out.

"Fuck no!" Undyne cried, giggling a little. "It was amazing! I've just... never felt that happy, before!" She kissed Alphys's nose. "And it's because of you, silly!"

Alphys blushed redder, and she smiled. "E-er, well... if-if you liked it, th-then that's all that matters..."

Undyne stared at her, love and adoration striking her heart so hard she bit her lip. She pounced on Alphys again, only this time, it was with a kiss - one that lasted quite a bit.


	25. Mirror Sex

**Notes for the Chapter:**

> I know I'm behind again, but I was having severe health issues. I'm gonna catch up!
> 
> Also, credit for Alphys's eyes goes to Khalliys, as it was her idea that Alphys had light eyes, light enough to be mistaken as the whites of her eyes. Khalliys has the best ideas and deserves all the credit for it. Thank you for being so inspiring!
> 
> Also, language warning: I use the word "cunt" in this chapter, but not as an insult. Rather, I use it as a word of compliment, as it used to be the ultimate term for a vagina. So Undyne uses it in that context - the most flattering term - and not the modern bastardisation of it. If I ever use it again, it will ALWAYS be in that way, and NEVER in the insulting way. In ANY of my fic. I don't use the word lightly - and I use it to make it count.

When they were undressing for bed, Alphys caught a glance of herself in the full-length mirror and sighed, stopping in front of it in just her bra and underwear. She frowned, put her hands on her hips, and moved from one side to the other, sighing again.

She didn't like what she saw. At all. She was short, fat, and pale. She had stretch marks along her arms, thighs, belly, back - pretty much everywhere. She also had scars along her wrists, ankles, thighs, and feet.

She glared at herself, her eyes blazing with hate.

She wanted to be a better woman for Undyne. She wanted to be beautiful and sexy for Undyne, who was beautiful and sexy without even trying. Alphys tried to exercise, even special types for her body type, but she could either never stick to the regime of strict diets to see it through.

Most of the time, she could tolerate her body. It didn't give her much trouble despite the stereotypes that came with her shape, and she was actually rather strong - especially in her legs.

But the rest of her body... she had issues with. She liked her legs, true, but not her thighs - thick ones that rubbed together - and perhaps she liked her shoulders - but not her back. She lowered her head, one hand fussing with her bra strap, her eyes on her feet. Maybe she could get some work done?

Undyne, unknown to her, was watching her - and already naked and waiting in bed for her. (She had _plans_.) Watching her wife looking at her body that way made her feel so sad. She loved the way Alphys looked. Sure, she wasn't perfect, and Undyne knew that. But Alphys was perfect _for her,_ which was the entire point (especially with those _plans_ of hers).

With a slight frown, she slid to her feet and went to Alphys's side. Immediately, upon seeing Undyne naked, Alphys's face changed. It went from pure admiration - to self-loathing once again. Undyne felt that strike her heart; she didn't realise that her own body could make Alphys feel self-conscious.

Well, now was Undyne's chance to fix that.

Alphys lowered her head and turned away, going red, before she muttered an apology and started moving away.

"Hold it, nerd," Undyne answered, grabbing her around the waist and lifted her up, then placed her back down in front of the mirror, standing right behind her with her arms around her waist, kneeling down to make it easier for both of them.

"Look at yourself again," Undyne said, and Alphys sighed and looked back up, her eyes settling and her frown increasing. "See, that? That right there? That shouldn't happen, Alphy."

Alphys snorted and looked away, unsure how to even begin to respond to that. It was all she knew how to look at herself.

"You wanna know what I see, my love?" Undyne asked softly, kissing her cheek gently. Alphys bit her lip, then nodded slowly, her tail reaching out and wrapping around Undyne's waist.

Undyne reached around and cupped her hands over Alphys's pale cheeks, holding them gently. "Here, I see a cute, pleasing face, one filled with love and yearning, of pain and sadness, yet one that still tries to stay happy for me."

Alphys stared at her through the mirror, her eyes going wide, still speechless - perhaps even moreso, now.

"This face..." Undyne smiled wider, her eye sparking. "I loved it the moment I saw it, looking up at me in shock and slight fear, but also something else, intrigue and curiosity--,"

"Attraction," Alphys blurted, blushing and closing her eyes. "I was attracted to you. I'd seen you around on-on the feeds, and-and I--,"

"I know that," Undyne replied gently, kissing her other cheek. "I know that _now_ , anyway. And to this day, this face has kept me in love for years, now. Your beautiful, expressive and almost translucent eyes, like prisms, really, a colour I could never describe, so shining and bright, and so warm - so warm! - every time they land on my one busted and cranky eye..."

Alphys laughed a little, sobbing faintly, her eyes closing for a moment, stricken by these words. She reached up and grabbed one of Undyne's arms tight.

"Th-thank you," she whispered. "But your eye isn't busted, Undyne."

"I'm not done," Undyne replied, surprising her. She moved a hand and poked the tip of Alphys's nose, surprising her into wrinkling it and giggling. "I like this nose, here. It's so cute. It makes you snort when you laugh, and snore when you sleep - which I oddly find soothing, believe it or not - and its sensitivity..."

Undyne laughed, and Alphys did a little, too, as it was a long-standing joke between them. Alphys's sense of smell was acute, and she could smell out anything - food, perfume, soap, shampoo... And every time Alphys caught Undyne's scent, she always blushed and asked her what she was wearing - and always was always surprised when Undyne insisted that she never wore perfume (which was true).

"It adds such character to your face, too," Undyne went on, and Alphys snorted and looked away. "It does! You're so cute with it! I wouldn't know, I smell through my gills, but you have a great nose."

Her fingers trailed lower and traced Alphys's lips slowly, tickling them and making Alphys blush. "And your mouth," Undyne murmured, her eye softening. "God, I _love_ your mouth. I love your _smile_ , especially when you show your teeth."

"I hate my teeth," Alphys admitted, her voice tight. "I hate them. I have buck teeth and they're stained from coffee."

"Shush," Undyne answered easily. "I love your smile. I love how your teeth stick out, just a little, because that promises more smiles to come. Plus..." She grinned slyly. "I love how they feel against my skin."

Alphys blushed deeper, shifting a little. "Undyne... Really?"

"Yes, really, you nerd!" Undyne replied easily, again. She slid her hands back up along her head, tracing the smooth, bare skin, before running her fingers along the spins slowly. "You have a wonderful head, too," she added. "You always say that you wish you had hair, and while admit you look damned adorable in wigs, I like you just this way. It suits you, and I see more of your beautiful face, too."

Alphys stared at her, her lips trembling. How did Undyne always know the perfect things to say? It was true that she used wigs to hide her face when they cosplayed, absolutely true: the longer the wig, the happier she was, as there was more she could hide. But Undyne had just easily and casually reassured her that she needn't. And it struck her heart.

Undyne noticed, and kissed her cheek again, before she moved her hands down much lower, this time - to her back. She unhooked Alphys's bra, and for a moment, Alphys debated protesting.

But then, she realised that wanted to hear more. She wanted to know more. She truly had trouble at times understanding why Undyne could find her so appealing, and here she was, telling her. So with a shy look, she shrugged her straps off of her shoulders, and Undyne slipped the bra off and tossed it to the floor.

Then, her eye lowered down and took in Alphys's now-naked breasts, and something in her eye glowed. Alphys watched her, her heart racing and her hands shaking at her sides, fighting the urge to use them to cover up.

"God," Undyne whispered, surprising her. Undyne gently slid her hands forward and cupped them gently around Alphys's breasts, her palms covering her nipples. Alphys closed her eyes and leaned back a little, and Undyne closed her eye for a moment, too, loving the feel of that.

"Alphy, your breasts..." Undyne murmured, still cupping them gently.

"Th-they're too... big..." she mumbled in return.

 _"Fuck_ , no," Undyne answered. "They're big, yeah, but _too_ big? No way. They're amazing. They're so soft, and so beautiful." Alphys opened her mouth, but Undyne interrupted. "No, Alphy, your nipples are not too big, and no, Alphy, they do not sag any more than they should. Don't even."

Alphys bit her lip, going scarlet, but she did reach up and cover Undyne's hands with her own, and Undyne smiled again.

"I love them," Undyne continued, her voice a little husky. Alphys looked at her and noticed her cheeks were pink. "They're beautiful. I can never get enough. They suit you so well, Alphy. And I love how sensitive they are, and how touching them makes you a puddle in my arms - like right now."

Alphys smiled shyly.

Undyne then slid her hands down to Alphys's belly, and Alphys looked away. Undyne nudged her face back with her cheek, but she wouldn't look.

"My love," Undyne murmured. "You have a beautiful tummy."

Alphys suddenly choked out a laugh. "Tummy?" she echoed.

Undyne nodded, grinning again. "Hell yeah! I love it! I love how soft it feels, how nice it is just to rub my cheeks against it, how it shakes a little when you laugh so hard..."

Alphys giggled, both shy and embarrassed, but Undyne wasn't done. Her fingers slowly moved closer and traced the scars of stretch marks, and Alphys's face fell again.

"I like these," Undyne said honestly. "They're like the lightning you control. Like your body is imprinted all over with the stamp of your magic. They're cool. And touching them always tickles you, making you giggle in the best way!"

"Well, yes!" Alphys agreed. "You're _tickling_ me!"

Undyne laughed, nodding. "And that's adorable! I also love how you just... own it. You don't let others win when they call you bullshit names."

"It still hurts," Alphys admitted.

"But you power through it," Undyne insisted, which was true. "And the clothes you wear... I love that you don't hide your plumpness, Alphy. It's so sexy."

"Being fat is _not_ sexy," Alphys corrected a touch angrily.

"Yes it is," Undyne answered sharply. "Because _you_ are sexy. You are big, and you are sexy. You can be both, dammit, and you are." She paused. "Alphy, I'm gonna be so shallow here, but..." Undyne sighed. "Your body was one of the first things I was attracted to. I loved it then, and I love it now."

”You're just flattering me!" Alphys protested.

"No, I'm not!" Undyne insisted, getting angry that she was being questioned at her most sincere. "Alphy, I mean every word I'm saying! I don't fucking lie to you!"

"But--!"

"No!" Undyne snapped. "I'm not done!" Alphys went quiet, and Undyne pulled her closer, softening her voice. "I love your weight, too," she admitted. "I love how solid you feel, the feel of you against me, in my arms, all of it. I love your weight, because I love the _weight_ of it. I love that all you have to do is sit on me and be the centre of my world. Your weight, the feel of you against me, is my comfort."

Undyne then blushed, realising how silly that sounded, but Alphys was eyeing her closely. "I'm... a _comfort_ to you?" she asked Undyne.

"God, Alphy, _yes,"_ Undyne agreed, kissing her shoulder and closing her eye for a moment. "So much. You're the comfort that keeps me sane, when I'm scared and angry and sad. You're the only one who can dispel it just by touching me."

Alphys bit her lip, her eyes filling with tears she couldn't control. "St-stop," she suddenly pleaded. "It-it's too much."

"Just one more thing, then, okay?" Undyne promised, and Alphys nodded, reaching up to brush the tears away.

Undyne then slid her hands down and moved it to her hips, sliding her underwear down her legs, before moving one hand back between Alphys's legs. Alphys blushed, then moved them apart a little, kicking her underwear away as she did, and Undyne's eye lit up, pushing her fingers between them. She slowly slid the tips along Alphys's folds, and Alphys closed her eyes, sniffling a little but leaning back again - this time for balance.

"Alphy," Undyne whispered, resting her head on her shoulder, her eye locked on Alphys's in the mirror. "I _love_ your cunt. I do." Alphys looked away, but again Undyne nudged her back. "I really do, Alphy. Not just because you know how to use it--," and here she wiggled her eyebrows, making Alphys smile again at last, "--but also... also.." She bit her lip. "The way it looks and feels."

"It's... not good," Alphys murmured, her voice tiny with sudden shame. "It's all uneven, and strange, and my--,"

"I'm not done, and if you interrupt me again, I'll make sure you can't speak for hours," Undyne growled, but Alphys blushed, hearing the true meaning of those words and wondering if she should keep talking, just to see it happen.

But Undyne was already talking, and as she spoke, her finger started to delve closer, effectively silencing Alphys. "The shape is unique," Undyne murmured. "I mean, it's not like I've seen enough cunts outside of porn to be the judge of them all, but I love the way yours looks, Alphy. I love the slightly longer than usual lips, the smooth feel, how wet and slick you get..." Her voice dropped low, and Alphys shivered, her knees feeling weak.

"Your clit," Undyne added, and suddenly her fingers were there upon it, and Alphys inhaled sharply, leaning back even more and grabbing Undyne's arm with both hands - only then realising that Undyne's other hand had cupped one of her breasts and kneading it. "I love your clit. I love how easy it is to make you do--," she flicked her fingers over it, and Alphys jolted, almost falling down with a strained cry, "-- _that."_

"Undyne..." Alphys suddenly growled out, her head lowering and her breaths getting short.

"I also love..." Undyne grinned, pulled Alphys back more, and angled her fingers up and inside of her. Alphys's knees immediately gave out, and she collapsed upon Undyne's lap - exactly as she planned. Undyne pulled her closer, and Alphys tilted her head back. Undyne then buried her fingers deeper and curved them up, and Alphys keened out. "...this button. I love how it makes you feel. I love how much pleasure it gives you."

"Undyne..." Alphys pleaded shakily, her claws digging into her arm.

"Yes," Undyne whispered, burying her face into the crook of her wife's neck, kissing there for a moment. "I love that it makes you say my name like that, especially."

She hooked her fingers up and rubbed harder, and Alphys groaned, leaning back and resting her head against Undyne's shoulder, her body starting to move in time with Undyne's fingers, stabs of deep pleasure hitting her hard and growing closer and closer together the longer Undyne continued.

 _"Undyne_...!" Alphys whispered breathlessly into her ear, pausing to lick it a little, unable to resist (Undyne shivered from it, holding her closer). "I'm close... Don't stop, please!"

Undyne chuckled into the curve of her neck, kneading Alphys's breast still and rubbing her palm over her hard, sensitive nipple slowly. "Good. But I have a favour."

"Yes," Alphys gasped _. "Anything."_

"Open your eyes and look at yourself, Alphy."

Alphys opened her eyes halfway, confused, but she leaned her head down and did, confusion making her forget. She saw herself and Undyne, Undyne holding her so close and tenderly as her hands worked her body, her eye on hers and blazing. Alphys stared at her, her mouth going dry, especially when she watched Undyne sink her teeth into her shoulder. Her eyes closed and she moaned, her claws gripping Undyne's moving arm deeper, but she suddenly felt Undyne shake her head.

"No, my love," she whispered, just as Alphys cried out again and squirmed, her breaths catching. "Open them again and look at _yourself."_

"I... d-don't... I c-can't... I l-look st-stupid when... I c-come," Alphys gasped out, keeping her eyes closed.

"You don't," Undyne corrected gently, slowing down her fingers a little - though she moved her thumb to Alphys's clit.

"Harder," Alphys blurted out. "Harder, please, _harder!"_

"I will," Undyne agreed, "if you open your eyes and look at yourself as you come."

Alphys whined a little, desperate as well as shy, but she nodded and opened her eyes again, looking first at Undyne, who smiled at her, before slowly moving her eyes to herself. The moment she did, Undyne suddenly held her tighter and moved her fingers harder and faster, her thumb moving along Alphys's clit alongside, and Alphys moaned again, loud and unrestrained, her eyes closing for just a moment before opening again.

She looked, her vision slightly blurry from how close she was, and saw herself - but not a self she was used to seeing. In Undyne's arms, her body was moving with abandon, not once pausing to meet Undyne's fingers so that they hit hard inside her every time. Her eyes were dark, and her face was red and sweaty, and soon, slowly, her body was reddening, too. Her body sometimes did that, blushed completely if she was overwhelmed, and it happened often during sex. Oddly, though, it seemed less to make her look like the tomato she always thought she looked, and more like someone completely overflowing with passion, one about to be set loose. Her body's movements were smooth, and not even close to clumsy, and while some parts jiggled and bounced, it was in a way that made it seemed like it was part of a dance, in which Undyne was the source of that music.

"Oh my god," Alphys squeaked out between gasps, now unable to look away. Undyne grinned, closing her eye for a moment, thrilled that Alphys was finally seeing herself, at last.

Soon after, Undyne felt Alphys's muscles start clenching, and she grinned, biting down on her wife's shoulder again as her fingers pumped. "Keep them open," she commanded, and Alphys nodded, looking delirious and loving it.

Then, finally, that building pleasure hit, and Alphys keened out Undyne's name, her voice breaking as she stumbled in her arms. She just managed to keep her eyes open, and watched as her body went red and clumsy - but in a completely different way. She went clumsy with the throes of pure pleasure, one brought on solely by her wife, and it was like that dance again, her body's movements slowing as the music faded into silence.

But it was her face that shocked her most of all. It was true that she tended to scrunch up her face when she came, the power of an orgasm so immense to her that it was without control, but what she'd never known was the one thing that kept her shocked.

 _She smiled._ And it was a smile of pure, unfiltered bliss. She'd never known, in all of her years, that she smiled when she came, simply thinking it was just further scrunching - but she was wrong -very, very wrong.

Undyne had known all along, because she got to see it each time - and finally wanted Alphys to see it, too.

What further shocked Alphys, however, was that it was actually a rather _nice_ smile. It was pure, without thought, and with full emotion, her mind not worrying about her teeth or her breath or any of it. It was her real, true smile, and she'd never realised she could look that way - _ever._

She collapsed backwards against Undyne, who caught her easily and held her tight in her lap, kissing her lips gently and rubbing her head, forehead to spines, slowly, her other hand slowly moving out of Alphys and onto her knee, instead.

Alphys returned those kisses weakly at first, so overcome and full of emotion that she could barely register it. Then, it swept through her, faster than her orgasm had, and she suddenly sobbed against Undyne's lips.

Undyne pulled back, but Alphys reached up and held her face in place, kissing her again and again, and with increasing further, despite the fact that she kept crying between them.

"Thank you," she sobbed out, her voice cracked and hoarse. "Thank you, Undyne. Thank you, _thank you..."_

She kept repeating it, over and over, until Undyne slipped her tongue into her mouth and licked Alphys's tongue still. Alphys's grip around her face tightened, and she growled, shifting and turning her body around in Undyne's lap, wrapping her legs around Undyne's waist hard - so hard that Undyne's hands reached up and held onto her back.

"Do... you... believe... me?" Undyne whispered between kisses, reaching up and brushing the tears from Alphys's cheeks with one hand. "I wasn't even done... I didn't even get to your ass...!"

"Undyne, I love you," Alphys answered tearfully, nodding. "You're my _everything_..."

"And you are mine, Alphy," Undyne replied, as Alphys leaned down and licked her neck - bringing a shiver to her. "I'm glad you finally see why, at last..."

Alphys moaned softly against her skin, then leaned against her hard and pushed her down onto the floor, kissing her lips again. "Make love with me, my love, my universe, my Undyne..." Alphys begged, and Undyne pulled her down and parted her legs, nodding with a hungry grin.

Alphys never forgot. Never. In her darkest moments, she called back Undyne's soothing words and actions, and was able to stay strong. Whenever she looked in the mirror and felt that loathing, she closed her eyes and remembered that smile - her own smile, the one she never knew she'd ever could make - and found herself calm down.

And for that, amongst other things, she knew she was Undyne's til dust.


	26. Striptease

Undyne was in a silly mood. She had been all day; it was something in the new spring air, the wet and clean breeze that spoke of warmer days and weeks of wonderful rain, of new flowers and fresh tea leaves, of baby animals and green plants...

Alphys loved it. She loved it when Undyne was hyper. Her eye shone and her cheeks were pink, and she was humming constantly if she wasn't speaking, and her speech was happy and bright. She practically danced wherever she went, and during classes, she was very chipper and actually went easy on the kids.

Alphys adored her.

That night, they were cuddling on the couch and watching anime. It was getting late, and they were so comfortable that Alphys was almost asleep, her eyes closing for longer and longer with each blink.

Undyne noticed, and was still rather awake. With a sly grin, she leaned down and kissed Alphys's lips gently. Alphys stirred, her eyes fluttering open and lighting up, her cheeks going pink as she smiled.

"H-hi," she murmured, reaching up and touching Undyne's cheek.

Undyne nuzzled it. "Alphy, let's go to bed."

"Mm," Alphys nodded, pulling her hand back and pushing herself up to her feet, stretching with her arms above her head and her tail rigid behind her, squeaking a little.

Undyne watched her with a rather toothy grin, and when she stood up, Alphys smiled up at her, her tail wagging. That did it for Undyne, and with a laugh, she scooped Alphys up into her arms and raced towards their bedroom, making Alphys giggle and cling to her tight, Undyne's mood catching.

Undyne tossed Alphys onto the bed, making her giggle even more, before she pounced upon her, pinning her to the bed and kissing her lips, her tongue immediately snaking out and pushing between Alphys's still giggling lips. Alphys purred, wrapping herself around her and kissing back, tugging on Undyne's clothes clumsily.

Undyne, however, reached for hers, instead, and managed to get Alphys naked before Alphys could even get her shirt off.

"Undyne...!" Alphys cried, only to be silenced with another deep kiss. Alphys melted beneath her, the sensual feeling of Undyne fully clothed and pressed against her naked body distracting her pleasantly.

Then, Undyne pulled away and slipped down, capturing one of Alphys's nipples between her lips, one hand moving down and sliding between her legs, tickling her thigh a little before she moved her fingers along her folds slowly, loving that she was already so slick.

Alphys squirmed with a sharp gasp, her eyes closing and her hands reaching for Undyne, one grabbing her other hand and tangling their fingers together, the other tangling in Undyne's hair, pulling it free and tossing the elastic away.

"Undyne," she murmured, her voice already thick. "Please?"

Undyne looked up at her and grinned around her nipple, grazing it lightly with her sharp teeth, and Alphys shuddered, her skin breaking out in gooseflesh. Undyne then moved away, moving down and kneeling between Alphys's legs - Alphys parting them the moment she got close enough - and diving right down, burying her face between those delightfully thick thighs, her tongue landing right on Alphys's clit and licking close.

Alphys arched back, her hands clutching tighter with a deep growl, her eyes rolling back before closing. "Fuck!" she blurted out with surprise, blushing right after, as she didn't use that word as often as Undyne. "S-sorry!"

Undyne, however, chuckled, a vibration Alphys felt, before she slid her fingers deep within Alphys and rubbed deep, still focusing her tongue on her clit. Alphys cried out, and Undyne was immediately thrilled.

At this rate, for Alphys, it took very little time for her to come, as Undyne had gotten her hot and bothered very quickly. Within minutes, she was crying out Undyne's name, her hand holding Undyne's so hard they both shook, and she accidentally tugged on her hair, but Undyne didn't mind.

When she relaxed, gasping, Alphys whispered, "Undyne, I-I st-still w-want you..."

Undyne raised her head and grinned, looking thrilled again, and Alphys smiled back. Undyne then pulled away and stood up, surprisingly Alphys into shakily sitting up, confused.

Undyne then flashed her widest grin and started to undress.

She grabbed the hem of her shirt, shifted and rolled her hips slowly, and started to slowly pull it up and over her stomach, revealing it inch by inch. Alphys watched every move, her hands clutching her knees tight and her tail wagging slowly, her eyes wide and her face red.

Undyne raised an eyebrow, then threw her shirt off over her head, holding it out for a moment on one hand and twirling it before letting it drop to the floor. She then rolled her hips again in the other direction, moving her hands over her stomach and up to her own breasts, cupping her hands over them and licking her lips, leaning down a little and pushing them up, so that Alphys could see their curves closer.

Alphys bit her lip, her tail wagging faster, and Undyne leaned back again, standing up to her full height. She slid her hands up from her breasts to her loose hair, tangling her fingers into it and pushing it back from her face, tilting her head back and arching her back, so that again Alphys caught a full glimpse of her breasts.

"Undyne..." Alphys squeaked out, and Undyne raised her head, her hair following and falling back into her face and over her chest, curving around her erect nipples, and suddenly Alphys envied her hair for that very reason.

Undyne said nothing, however - just flashed her a dazzling grin, and Alphys giggled. Nothing was much better than seeing that grin, really.

Undyne reached forward and started undoing her jeans, undoing the fly and pulling down the zipper, all of her moves slow and deliberate. She pushed them down over her hips, then did a little wiggle, both of her rear and her hips, before turning around and sliding them down over her backside, revealing her underwear - black, and in a sexy cut, Alphys saw - before she did another wiggle, this one slow, rolling her hips again and turning back around slowly, kicking her pants to the floor and holding her leg out for a moment, wiggling her toes and making Alphys giggle again.

Then, Undyne spread her legs and reached down, hooking her thumbs into the waistband of her underwear, her fingers moving flat and reaching lower. She stared right into Alphys's eyes and grinned, licking her lips again, and she slowly moved them down, revealing soft, curly red hair. She pulled one hand away, keeping her underwear halfway down, and touched those curls slowly, her eye closing briefly as she did.

Alphys's eyes widened, and she squirmed, one hand of her own slipping down between her own legs without her really noticing. Her tail was no longer wagging, but a tight spiral, and her mouth was closed tight, still smiling.

Undyne turned around again, resuming her slow reveal, this time showing a great deal of ass. Alphys smiled wider, appreciating this very much, and Undyne slid her hands down over her cheeks and squeezed them briefly with a slight smack, bringing another giggle from Alphys.

Then, finally, she shimmied out of her underpants and kicked them away with the other leg, doing the same leg-toe dance with another wiggling of her eyebrows.

Alphys stared up at her, shaking a little. Her hand was quite busy with herself, now, but the other was still on her knee, her claws digging in hard.

"Like my little dance?" Undyne wondered finally, standing there with her hands now on her hips.

In reply, Alphys lunged up, threw her arms around Undyne's waist, and dragged her down to the bed.

A perfect answer, really.


	27. Tickling

It was no secret that Alphys was ticklish.

But the secret was that Undyne was, too.

When Alphys found out, she was delighted. When tickled, Undyne didn't laugh - she giggled, a high-pitched string of unbroken giggles that made her squirm and shriek in-between strings. It was the cutest sound that Alphys had ever heard, and she loved to exploit it at random moments. 

But once, she employed it another time, and it was an excellent gamble.

* * *

"Mm..." Undyne murmured, tilting her head back against the pillows, her nails digging into Alphys's shoulders. "Fuck, you are so good at this..."

Alphys blushed, leaning down to kiss her neck - as now it was nicely exposed - and Undyne gasped, grinning and squirming a little. 

Alphys was moving at a slow pace, the day having been long and frustrating, and both needed a nice, wonderful distraction from it all. They hadn't even had dinner yet, but it didn't matter; in a way, they were working up their appetite. 

"Just..." Undyne growled out, her teeth gritted. She arched back, grinding her hips up against Alphys, and she felt Alphys inhale sharply and nip a little at her neck. "Yes..." Undyne concluded. Alphys smiled and shifted, so that she could adjust to meet Undyne's needs, and her wife smiled with a short cry, her legs wrapping around her even tighter. 

Then, Alphys got an idea. She smiled wider, moving down closer to press fully against Undyne, and again Undyne cried out softly, moving to kiss her. Their lips met, and Undyne purred in deep satisfaction, becoming more and more insistent as they moved together. 

Alphys, by now, knew Undyne's signals very well, and could hear, in both her voice and her breaths, that Undyne was getting close. She felt a small thrill, one she always felt whenever she came to that conclusion, and she kissed Undyne deeper, lengthening her strokes and pushing her hips harder. 

"Yes," Undyne whispered against her lips, adding another thrill. "God, Alphy, _yes..."_

"Mm," Alphys replied, making her laugh a little and kiss her nose, the laugh ending in a small gasp. 

"Don't stop," Undyne suddenly begged, clutching at her and squirming again, burying her face into Alphys's shoulder. _"Alphy, don't stop!"_

"Do you see me stopping?" Alphys wondered teasingly, and she laughed again, the sound strained. 

"Thank you, _good,_ fuck, fuck, _fuck! Ah! Alphy!!"_ Undyne bit down onto Alphys's shoulder, crying out over and over, now, as her orgasm hit her hard.

Alphys quickly raised her hands up and reached right under Undyne's arms - and started tickling.

 _"Oh my god!"_ Undyne shrieked, before she exploded into strained, shocked giggles, her hands going up to try and stop Alphys, grabbing at her wrists. She gasped in shock, suddenly filled with duelling pleasures: her orgasm, and the tickling. It was the strangest feeling, thrilling and overwhelming - but also incredible. _"Alphy, holy fuck!"_ She shrieked it out, then started giggling again, tears coming to her eye.

Alphys giggled, too, pulling her hands away once Undyne begged out, her voice breaking, "Mercy, Alphy!" Undyne reached up and batted at her shoulder with her fist lightly, still laughing. 

"Alphy, you demon!" Undyne shouted, laughing between each word. "You evil, evil tickling _demon!"_

"Bet it felt good, though," Alphys teased, leaning down and holding her close, kissing her cheeks. 

"Oh my god, Alphy!" Undyne cried, pulling her closer. "You gotta fucking try it, let me try it on you!"

Alphys laughed, but Undyne was serious, and when Alphys found herself tackled, that was only the start. 

And Undyne was very, very right, indeed.


	28. Overstimulation

"Fuck," Undyne gasped, leaning to the side and collapsing, her eye closed and her body full of pleasure, grinning. Alphys murmured an agreement, immediately turning over and curling up into her arms, resting her hot cheek on Undyne's chest and listening to her heart racing. 

Alphys then blushed, her own body still humming, but oddly, she still felt hungry. She shifted closer, one hand moving down and cupping around Undyne's breast, brushing her thumb slowly over her still-hard nipple.

"Alphy," Undyne breathed out, shifting a little. 

Alphys looked up at her with a sly smile, but Undyne's eye was still closed - and she was still smiling. She sat up a little and moved closer, leaning her head down and licking Undyne's other nipple. 

"Alphy..." Undyne murmured, her hands going to Alphys's back with a small gasp. "We just..."

"More," Alphys whispered against her nipple, rolling over onto Undyne, straddling her gently and kissing up to her neck slowly. Undyne exhaled slowly, moving to part her legs a little, her arms wrapping around her wife. 

"More," Undyne agreed, her voice low and hoarse. Her body was heavy and lethargic, still sensitive and raw, but Alphys was like pure catnip to her, and she a ridiculous tabby. 

Alphys reached down between them and adjusted her body so that their clits met again, and they both moaned softly, clinging onto each other tightly. Their bodies hummed again, their skin still very sensitive and hot. 

Everything felt heightened, they both realised, as they moved together again, a tangle of slow-moving, steadily-growing bliss. Alphys buried her face into Undyne's shoulder, and Undyne did the same, her nails digging into her back, as she felt claws dig into her hips. Every jolt was like a knife, making them both shudder and cling tighter. 

"Ah," Alphys murmured, her voice breaking. "M-maybe it's t-too much...?" 

"Yes," Undyne agreed, her voice tiny. "But don't stop."

"You-you sure?"

"Don't stop!"

Alphys nodded, unable to speak, now, but she increased the pace, suddenly curious. They both jolted, the feel like an edge of that knife, but they also felt a shiver of pleasure, one that grew as they moved, and it soon started to overpower that edge.

"Oh god," Undyne gasped out, her voice a mewl. "Oh god, Alphy. _Oh god!"_

Alphys gritted her teeth, unable to speak, but she tried - and only got out a long, thick moan. 

It was amazing, almost like casting too much magic at once, only to have that spell backfire and not only return that energy, but with extra added to it. All either woman could think about was the other, and they were so overwhelmed by that that there was nothing else in the whole world but themselves. 

They kissed, then, and it was amazing; it was like electricity, the warmth and shock of it so sharp that they both wondered if Alphys had accidentally used magic. But she hadn't - their senses were sharp, not their magic.

It didn't take much longer after that, Undyne succumbing first - and hard. She keened out, her voice hoarse and breaking, and she stiffened, her hands scrabbling at Alphys's back and scratching a little. Her eye rolled up and shut tight, and her orgasm swept through her so hard she cried out with each breath, her entire being overtaken by that pleasure. 

Alphys, feeling Undyne come beneath her, soon followed, the feel of Undyne's body writhing sending her off into a daze of her own. She, too, cried out, her whole body seizing up with that bliss, and her claws dug into Undyne's hips hard, but Undyne didn't even feel it. Alphys didn't even know she did it, so close to blacking out that she staggered, and Undyne grabbed her and held her tight, not wanting to let go for a second.

When it passed, they both seemed to deflate, gasping and crying out as they clung to each other, feeling so sensitive and raw that even the breaths upon their skin felt intense. They didn't move, everything so clear and bright, just intent on holding each other and regaining their breaths.

Then, Undyne whispered, "That was hot."

Alphys giggled tiredly, kissing her chest and making her shiver and bury her face into the top of Alphys's head, which in turn had her shivering. 

They then fell asleep, unable to stay awake after something like that. But it was a good sleep - that was for certain.


	29. Cunnilingus

Alphys loved going down on Undyne. It was one of her favourite things that they did intimately, and Alphys always tried to do it each time they made love. It always made Undyne laugh, how insistent she was to go down on her, but Alphys could never resist.

There were times, however, that Alphys got carried away - mostly for good, true. But one incident stood out amongst many, one that Undyne never let her forget.

They were eating dinner rather calmly - or so Undyne thought. Alphys had been looking at her with red cheeks, true, but sometimes, that just meant she was looking at Undyne. 

So when Alphys suddenly grinned and disappeared beneath the table, Undyne was confused.

For a moment.

She'd worn a skirt that day, as it was hotter than either of them could remember. Alphys had been watching her all day, really, with red cheeks - and Undyne figured it was the skirt.

And it was. Very much.

So when she suddenly felt her legs being parted and a kiss grace her inner thigh, she jumped - but then laughed. "Hungry for something else?" she teased. "Or just thirsty?"

Alphys kissed her other thigh, her hands slipping under the skirt and reaching for the shorts that Undyne wore beneath them. "Mm," she replied helpfully, pulling them down and following them with Undyne's underwear.

Undyne was suddenly conflicted. She wanted to eat, true. But now she also wanted Alphys to continue. With a raised eyebrow, she shifted and spread her legs a little, before she took up a forkful of food and ate it. 

Alphys knelt down, her heart racing, and moved between Undyne's legs and beneath her skirt, slowly marking a path with kisses along her thigh towards her cunt. Undyne shifted again, the blood rushing to her face, and Alphys felt it and dove in at last, immediately licking those folds apart and diving her tongue deep into Undyne's centre.

"Fuck!" Undyne cried, jolting and almost dropping her fork. She then laughed, tilting her head back and gasping. "You are so _good at that!!"_

She heard thumping, and knew Alphys was wagging her tail in reply, which made her laugh again. 

Then, of all things, there was a knock at their door. 

Both women froze, Undyne turning and glaring at it, while Alphys raised her head for a moment and hesitated, her hands still on Undyne's knees.

"Expecting anyone?" Undyne asked her.

"N-no," Alphys admitted, her voice a little husky at the edges. "Don't answer."

And suddenly, she was back and licking deep again, and Undyne gasped, dropping her fork and squirming. "Shit," she whispered. "You're right. Don't stop."

Alphys grinned and licked upwards, running the tip of her tongue along Undyne's clit slowly, flicking its tip, and Undyne lowered her head and growled. 

There were more knocks at the door.

Then, "Undyne, Alphys? It's Toriel, my dears. I wanted to discuss the latest meeting with you? You seemed upset with the budget."

"Shit!" Undyne repeated, only this time in a completely different way. "Alphy, quit it, we need to-- it's-- _aaah!"_ Undyne's voice broke, and she reached beneath the tablecloth and tried to grab hold of her wife, but Alphys just shifted closer and increased the pace. 

And for a moment, Undyne stopped caring about the door. She gritted her teeth, feeling a jolt of pleasure slip through her as she got closer. "Alphy..." she murmured. When Alphys squeezed her knee, she was going to tell her to stop, but she said, instead, "Don't stop..."

"Girls? Are you home?" Toriel called with a couple of knocks.

"Yes," Undyne called, struggling to keep her voice calm. "Come in!"

Alphys froze for a moment, before Undyne tightened her legs around her face, and she almost laughed before she kept going, squeezing Undyne's knee again. She looked to the sides and saw that the tablecloth hid her perfectly, and she curled up and didn't stop.

The door opened and Toriel walked in, smiling and holding a file folder. "Hello, Undyne!" She paused. "Oh, dear! You're eating! I'm sorry, I can come back!"

"No, it's cool," Undyne replied, her voice a little tight but still calm. She smiled. "Sit down, we can keep it brief."

Toriel did, sitting between Undyne and Alphys's places. "Where is Alphys?" she wondered, looking around.

Alphys grinned, curious, too, and she angled her tongue upwards again, slowly tracing Undyne's clit. She felt Undyne's foot curve around her thigh tight, and she fought the urge to giggle. 

"Alphys is just in the washroom," Undyne said carefully, finding that she really needed to focus in order to speak properly. "You just missed her."

"Oh, well, this won't take long, like you said," Toriel replied with a smile, opening the folder and putting her glasses on as she sorted through it. "I know you had concerns about the equipment budget."

"Yeah," Undyne grunted out, shifting in her seat a little. "We need better balls. The ones we have are shit, and deflate every week."

Toriel wrote that down, looking concerned. "I didn't know that," she admitted. "Did you tell someone?"

"Duh," Undyne answered, using sarcasm to mask the fact that she was getting really close, and was having trouble keeping her breaths steady. "They said that they'll get back to me once they talk to you about it."

Toriel sighed, looking annoyed. "They did not," she said flatly. She looked up - and saw Undyne's expression: her face was bright red, her eyes closing for long blinks, and her hands were gripping the side of the table so hard they shook. "My dear, are you alright? Are you ill?"

"N-no," Undyne mumbled. "Just... annoyed, too."

"Alright," Toriel said, raising an eyebrow. "Do you happen to know what Alphys was concerned with?"

"Y-yeah," Undyne nodded, lowering her head. "She was worried that the lab wouldn't have enough... m-money..." She shifted again. "To keep the chemicals stocked... all year."

Alphys was so surprised and pleased that her tail wagged before she could stop it. Luckily, she stopped just before Toriel could hear it, and instead increased the pace of her tongue as a kind of reward. Undyne's legs immediately tightened around her harder, and her feet - both were on her thighs, now - dug in their heels, shaking a little. 

"Oh!" Toriel wrote that down quickly. "Yes, I agree with her. It didn't seem like enough money, to be honest. I'll talk with them again. In the meantime..." Toriel placed a hand on Undyne's, startling her into looking up. "Do get some rest, please. I'd hate to see you get sick."

She stood up, surprising Undyne. "It's alright, that's all I needed," she explained cheerfully. "I'll see myself out. See you tomorrow, and tell Alphys I said hello."

"Of course!" Undyne agreed, nodding again.

Toriel smiled and left.

Undyne shouted out, _"Fucking fuck!"_ and arched back in her seat, her eye closing tight. "Don't you dare stop now, Alphy!" she added. "I'm so fucking close I could _scream!"_

Alphys raised an eyebrow, secretly hoping that she would scream, and changed her gestures in order to see if she could get her to do so. Undyne cried out, jerking against her, and with several shouts of Alphys's name, she came, almost falling out of her chair from it. 

Alphys pulled away slowly, then crawled out from under the table, bright red and looking very, very triumphant. Undyne glared at her, panting hard, before she jumped from her chair and tackled Alphys to the floor, kissing her so hard she laughed.

(Toriel, once she closed the door, had started walking when she heard Undyne's shout. She snorted, then grabbed her phone and texted Asgore: _"Under the table. You owe me fifty gold."_ Then, laughing under her breath, she made her way down the hall and to the elevators, her face pink and her eyes bright.)


	30. Foursome (Wife Swap)

**Notes for the Chapter:**

> A few notes on this piece:
> 
> I've written it as both the second last and last prompts, as it got very long and truly does include more than two prompts from the previous list.
> 
> This was also a request, in a way. As well as entirely my fault, as I planted the seed for that request(s). SO IT'S FINALLY UP, OKAY?!
> 
> Kinktober was fucking fun! I may do this again next year!

It was ultimately Toriel's idea, though Asgore would later admit to being just as interested in it as she.

It had been almost a decade since the barrier had come down, and they'd been reconciled for nine years. In those years, they'd watched Frisk grow up, a joy in itself. But they'd also grown closer to the other monsters who played a major part in that growing up - most importantly, Alphys and Undyne.

Over those years, both former monarchs had grown close to the two, in different ways: Alphys had become a dear friend to both Toriel and Asgore, one who would never hesitate to defend them. Undyne, who had already been close to Asgore already, found a fun friend in Toriel, as she loved to encourage her to let loose and have more fun - something Toriel was easily swayed to do when in her company.

It was after such a night that Toriel, over afternoon tea, suggested her idea to Asgore. She said it so calmly, in such an easygoing way, that for a moment, Asgore was certain he'd misheard her.

He choked on his tea, then looked up at her with wide eyes. "What was that you just said?" he asked weakly, feeling his face burn.

Toriel smiled, and it was a gesture that was so full of hunger and eagerness that Asgore was spellbound.

"I said," she replied, "we should see if Alphys and Undyne are interested in swinging with us."

It was then that Asgore felt an odd sensation from behind his nose, one that grew to be quite warm - and soon, he realised his nose was bleeding. He spluttered out nonsense, reaching for the nearest tea towel, and he heard her burst into delighted laughter.

But he protested. "Tori, dear, I don't think they would. Especially Undyne. She looks up to me, you know."

"I do know," she agreed. "But I also know that, at one point, Alphys was quite smitten with you, and I do sometimes catch her glancing at you in a way that suggests some of that fondness is still there - and still smouldering."

"Alphys?" he repeated, surprised by this revelation.

"Yes," she said. "And Undyne, herself, well..." She blushed a little, though she smiled. "She certainly loves to flirt with me when we're tipsy together!"

Asgore kept the towel firmly pressed to his face, now, knowing that her elaboration only made things worse for him.

"So I was thinking," she went on, putting a hand to her cheek, "we could ask them to swing with us. You would, of course, be with Alphys, and I with Undyne."

Asgore at this point realised one tea towel wouldn't be enough.

* * *

"Uh," Undyne said, her voice small and her eye huge. Her face, however, was bright red. "You want to do what with us?"

Alphys was in a similar state, though her hands were held up in front of her nose - just in case. She envied Undyne, really; she could find no words to even begin to try to reply to Toriel.

Asgore was blushing, as well, but he was glancing at Alphys with affection, as he recognised the gesture and found it rather endearing.

"We're all adults, here," Toriel replied. "I know you find my husband attractive, Doctor."

Alphys looked panicked, now. "B-but I would never-- it's n-not like I w-would-- I would never cheat--!"

Undyne touched her hand gently, calming her rather effectively. "I know," she said to her. "I think we all know that."

"Who said anything about cheating?" Toriel countered. "Again, we're all adults. And, Undyne..." Now Toriel blushed, glancing at Undyne with shyness - and affection. "I must admit, I am rather keen on you - and perhaps you're keen on me...?"

Undyne went scarlet, her mouth going tiny in surprise. Alphys looked over at her, a small smile suddenly on her lips and her eyebrows raised.

"I knew it," she murmured, and Undyne lowered her head, making sure her bangs hid as much of her face as possible.

Toriel lit up and looked at Asgore with a smile, and Asgore smiled in return, nodding.

"So, ladies, would you be up to it?" Toriel pressed, looking back at them and beaming.

Alphys blushed again, and Undyne raised her head, her eye wide. They looked at each other, their eyes meeting, and something clicked between them: trust, intrigue, and... arousal.

"W-wait," Alphys suddenly blurted. "N-not in the same room, r-right? Separate rooms?"

Asgore blinked in surprise, and Toriel looked a little disappointed.

"If that makes you more comfortable, we can do that," Toriel replied gently.

Both Alphys and Undyne relaxed, nodding, and Asgore nodded, too. Clearly, Toriel had been the only one who'd wanted it all in one room.

"So, is that a yes, ladies?" Asgore wondered softly.

They looked at each other, then smiled faintly.

"Yeah," Undyne agreed, glancing at Toriel with a wide, toothy grin.

"Y-yes," Alphys added, shyly looking at Asgore, then sharing a faint blush with him.

"Well, then," Toriel replied, beaming again. She waved down their server, and from there, it was a blur.

* * *

When they got to the Dreemurrs' home, Undyne suddenly took hold of Alphys's arm and pulled her back, leaning down close.

"Are you sure about this, Alphy?" she asked gently. Alphys looked up at her, and Undyne added, "I mean, you know this isn't anything that will break us up, right?"

Alphys shook her head right away, taking hold of her hand tight. "No, of course not!" she agreed. "Honestly..." She hesitated, but Undyne smiled, so she went on. "I've... been curious."

"Me, too," Undyne agreed.

"Plus, I don't blame you," Alphys added, smirking. "Toriel is very beautiful."

Undyne blushed, looking away for a moment, before she looked back. "But, Alphy," she said, looking a little panicked. "You're way more beautiful."

Alphys giggled, and Undyne relaxed. "Don't tell Toriel that!" she advised, and Undyne laughed, too.

Then, they held hands, and caught up with the Dreemurrs, closing the door behind them.

* * *

"Gorey, dear, why don't you use our room?" Toriel wondered, her hand on Undyne's shoulder. "And Undyne and I will use the guest room."

Alphys blushed when she felt Asgore touch her back gently. "Are you sure? Ours is the bigger room."

"And you are the biggest amongst us," Toriel replied. "I think Undyne and I can make due."

Undyne grinned and nodded.

"Alright, then." Asgore smiled, leaned close, and kissed Toriel's cheek, something she returned. "Have fun."

"And you," she replied, her eyes dancing.

Alphys glanced at Undyne, who was already looking at her. They both exchanged amused grins, before Alphys winked, and Undyne laughed.

* * *

Toriel sat down on the double bed, her cheeks pink but her eyes still bright. She looked up at Undyne, who stood in front of her shyly, also blushing. She scratched the back of her head, unsure of how to begin, until Toriel patted the bed beside her. Undyne sat down, then glanced at her.

Toriel reached forward and touched her cheek gently, something that had Undyne blinking from. The gesture was gentle, and full of warmth, and it was one that felt nice. Undyne smiled, leaning closer, and the two kissed.

For both, it was different, as they were both used to a single partner for so long. But it was the kind of different that was malleable, the kind susceptible to change, and as it deepened, so did an ease between them.

Undyne reached up and took Toriel's face between her hands, her eye closing, as she parted her lips and licked slowly along Toriel's lips, finding them smooth and soft. Toriel shifted closer, her hands going to Undyne's shoulders, and she opened her mouth and touched her own tongue to Undyne's.

They both shivered, pushing closer to each other, before Undyne wrapped her arms around Toriel and pulled her close, so that the former queen had to straddle Undyne to keep her balance. Toriel's breath caught in surprise - and a sudden stab of arousal - and she kept her legs firm around Undyne's slim waist, sliding her arms around Undyne's neck.

"You're..." Undyne whispered between kisses, her hands slipping beneath Toriel's shirt and touching soft, downy skin. "You're so warm..."

"Fire magic," Toriel replied softly, smiling wide enough to show her fangs, and Undyne grinned in return, surprised by how well that turned her on.

They kissed again, and Undyne's hands moved up and landed on Toriel's bra. She unhooked it easily, parting it and running her palms over Toriel's back. Toriel leaned back and closed her eyes, sighing deeply. Undyne took advantage of that and leaned down, kissing her neck gently. Toriel shivered and clung to her for a moment, suddenly very overcome.

"Goodness," Toriel whispered. "You're very good."

Undyne smiled, gently nipping her neck. "I've good company," she replied honestly, pulling on Toriel's shirt.

Toriel leaned back and took it, and her bra, off, and Undyne's eye was immediately on her breasts. Toriel raised her head, blushing just a little, as Undyne's expression was rather flattering: her face went red, and she licked her lips, her eye darting between them.

"Damn," Undyne murmured, reaching up and cupping one gently. Toriel sighed and leaned forward again, her eyes closing, and Undyne kissed her cheek. "You're hot," Undyne concluded, and Toriel laughed, the sound surprised and shy.

"I'd love to see you, dear," Toriel admitted, and Undyne blinked, having been about to lean down and nuzzle one of those breasts. She then grinned, nodding, and sat up, throwing her shirt and bra off easily. She then leaned back to finally nuzzle, but Toriel stopped her, pushing her away and holding her by the shoulders.

Undyne blushed, especially when Toriel's gaze lingered over her breasts - and the queen's own blush deepened.

"My," she murmured. "They're wonderful, like a model's."

Undyne burst into laughter at that, her shyness vanishing. Toriel tilted her head to one side, and she explained. "Alphy said the same thing. She said, 'Everything about you is perfect! You're like a model pulled from a magazine!'"

Toriel laughed, too. "Well, she's right." She held up a hand, then paused. "May I?"

Undyne nodded, and Toriel reached down and gently cupped one of Undyne's breasts. Undyne closed her eye; Toriel's hands were very soft and warm, and it was like being touched by a blanket. Silently, Undyne reached out to touch Toriel, and when she did, she grinned: Toriel's breast was similar, just as soft, only smooth at her nipples. It was a very curious feel, but Undyne found she liked it.

"Kiss me?" Undyne whispered, opening her eye and looking at Toriel. Toriel smiled, leaned close, and kissed her.

* * *

"I-I'm not that great to look at," Alphys muttered, staring at her hands tangled in front of her. She refused to look at Asgore, who was sitting beside her quietly on the bed, listening. "And-and I've never been with a m-man, so I d-don't know exactly what to do. I-I mean, I know what to do theo-theoretically, but I've n-never done it, and--,"

Asgore reached forward and pressed a finger to her lips, silencing her. She looked up finally, her eyes wide, and they met his. They then softened, and she searched his gaze.

When that happened, something in Asgore opened up, and he realised something about himself: he did find Alphys rather attractive. She was plump, and sturdy, and had generous curves, and she was also sweet and kind, if shy. This close, seeing her face like this, made him also realise that he'd felt a deep tenderness for her for years, and to see it returned to him by simply looking into her eyes struck him deeply.

"Alphys," he said gently, lowering his hand and resting it on her knee. "Do you want to do this?"

"Yes," she said immediately, nodding. "Yes, very much. Asgore, I... I'm..." She hesitated, then sat up on her knees, put her arms around his neck, and kissed his lips. She lingered, but moved to pull away, and Asgore reached up and pulled her back, returning the kiss and holding her close, pressing her against him.

It was odd. Asgore had a beard, and it tickled and scratched a little when Alphys kissed him. But his lips were smooth, and it didn't hurt her - it was just different.

Asgore then pulled away gently, and Alphys didn't move for quite some time.

After a moment, she opened her eyes and murmured, "Oh..."

Then, she lunged for him, kissing him again hungrily and grabbing at the front of his shirt, unbuttoning it as fast as she could. Asgore grabbed her and tugged on her shirt, the fire in his blood flaring to life from the spark of their kiss.

It was strange, this passion. Neither had known such existed between them, but now, together, it was not only obvious, but overwhelming. But in the best possible way, they both agreed.

They parted briefly to get their shirts off, and it was then that Alphys suddenly started to hesitate. Her eyes landed on Asgore's chest, and she bit her lip. He was of a type that spoke of muscle going to seed, but still finding lovely definition remaining. He was covered in both white, downy fur and longer, thicker gold-white hairs closer to his upper chest and belly. Alphys blushed, because she realised she really like how he looked.

"Oh," she repeated, looking up at him shyly. He had been watching her, smiling at her expression and finding her endearing, and when their eyes met, she caught look of that and blushed deeper, not used to seeing that expression on anyone but Undyne.

"Alphys," he said softly, touching her red cheek. She smiled, and the gesture struck him again deeply. "Are you alright?"

"Yes," she agreed. "I'm... excited, and kind of overwhelmed... I'm shocked we're doing this... but it's a nice kind of shocked..."

Asgore smiled wider the longer she went on, still touching her cheek. "I agree," he admitted.

Alphys wagged her tail a little, her heart racing, and she fumbled for a moment before she unhooked her bra and shrugged it off, then looked back up at him.

His eyes had lowered, and he bit his lip, going over her breasts slowly. Alphys looked away for a moment, feeling embarrassed, but then she felt him cup one of them, and she closed her eyes, exhaling slowly.

"Lovely," he murmured, his voice soft.

Alphys stared at him, swallowing hard. "Asgore, you-you don't have to say th-that."

"No, but it's true," he replied easily.

Alphys bit her lip, especially when he cupped the other breast. She breathed shakily, losing control very quickly, and before he could blink, she grabbed hold of him again and kissed him, hard, bringing a surprised grunt from deep in his throat. She reached down and tugged at his pants, and that lit him up once more. When she tugged them down around his hips, he reached for hers, and she licked his lips apart, bringing another sound from him.

The moment she could, she kicked her pants off to the floor, then did the same for his, causing him to stumble a little before he caught his balance, his heart jumping excitedly when he felt her hands back on his shoulders, her claws digging in hard.

"Asgore," Alphys gasped out between kisses, "I want you, I really want you, I-I'm sorry..."

"Don't apologise!" Asgore protested, pulling back and holding her face in his hands. Alphys bit her lip, and he pressed his forehead to hers. "Don't be sorry, please. I want you, too."

Alphys blushed, blinking in surprise. "O-oh," she murmured, then wished she knew a better thing to say. "Th-thank you..."

Asgore chuckled gently and rubbed her cheeks, and she smiled, relaxing. "Kiss me again?" she asked, and he nodded and complied.

When his hands reached for her underwear, she didn't stop him.

* * *

"Mm," Toriel murmured, reaching up and touching Undyne's cheek gently as they kissed. Undyne purred against her lips, shifting closer, especially when she felt Toriel gently tease her nipple.

"For someone who hasn't been with chicks," Undyne murmured, "you sure know what they like."

"I am also a chick, Undyne," Toriel replied gently, and Undyne laughed. "So, you... like this?"

"Yes," Undyne agreed right away, her eye closing. "Yes, yes. You're... so soft..."

And she leaned forward, grabbing hold of Toriel and pressing her body against that softness, burying her face into her shoulder and nuzzling her neck.

"So soft," Undyne breathed out, smiling. Toriel pulled her closer and gently took hold of her chin, raising it. Undyne looked up, and they kissed, Toriel gently pushing Undyne down and onto her back. "Mm," Undyne added, shifting and wrapping her legs around Toriel's waist. Toriel pressed close and kissed Undyne deeper, still kneading one of her breasts. Gently, she shifted her hips against Undyne's, and Undyne purred, shifting back and surprising Toriel with how good that felt.

"Goodness," Toriel whispered, her eyes closing.

"Yeah," Undyne agreed, shifting again, and Toriel gasped softly. "Nice?"

"Very nice," Toriel agreed. "I'd... love more..."

Undyne grinned up at her. "Then get naked."

Toriel laughed, pulling back and sitting up, sliding down her skirt and tossing it to the floor. Undyne took the chance to not only take off her pants, but also her underwear.

Toriel peered at her, interested, and she noticed and laid back down, grinning. "Undyne, look at you, you have bush!"

Undyne burst into laughter, falling back on the bed and covering her face. "God, Toriel, you're fucking cute!" she blurted out.

Toriel blushed, surprised by how flattered she felt. With a smile, she slipped her underwear off, too, and Undyne noticed.

"You have a tail!" Undyne cried, pointing. "Why don't you show that, more? It's adorable!"

Toriel blushed deeper and smiled. "Undyne, you're making this old woman feel like a teenager again."

"Good!" Undyne replied, sitting up again. She leaned close, moving her hand along Toriel's thigh, and Toriel sighed deeply, leaning her head against Undyne's shoulder and closing her eyes.

"Touch me?" Toriel asked softly, her eyes still closed.

Undyne nodded, eager to do just that, and she slid her hand between Toriel's generous thighs, licking her lips as she did. Toriel shivered and parted her legs, and Undyne touched her, lightly. Toriel relaxed, one hand going up and touching Undyne's breast, and Undyne took that chance to touch her closer, intrigued.

Toriel, like Undyne, had hair over her cunt, too, but the same white fur that covered her body - just a little thicker and curlier. She trailed her fingers along Toriel's folds slowly, surprised when she felt wetness already, and she shifted, her internal reaction taking her off-guard - it aroused her immensely.

"What do you like?" Undyne asked her gently, her other arm around her back and holding her close.

Toriel sighed, smiling, and she murmured, "My clit, and inside, too. And both is the best."

Undyne chuckled. "You're like Alphy, then," she concluded. "I can't stand it inside too much. Not when you push the button, anyway. It feels too weird and intense for me. Inside is fine - Alphy has a great tongue - just don't touch that button."

"I love it," Toriel admitted. "Touch it all you want, please, dear."

Undyne nodded, kissing her cheek, and Toriel nuzzled her neck and rested her head back on her shoulder, her heart racing with anticipation and excitement - a beat Undyne could hear.

Undyne stroked her skin for a moment, then moved her fingertips higher, brushing them over Toriel's clit. Toriel jumped, burying her face closer, her other hand grabbing hold on Undyne's knee, and Undyne smiled, running her fingers along her clit slowly and closely.

"That's lovely," Toriel murmured. "You've lovely fingers, Undyne."

"Piano," Undyne replied.

"I'd... mm... like it if you..."

Undyne shifted closer and slipped two fingers between those folds, and Toriel smiled, nodding. She then did something that surprised Undyne: she trailed her hand down from her breast to her side, sliding them very lightly over her gills.

"Whoa!" Undyne cried, jolting. Toriel looked up and moved her hand away, worried, but Undyne grabbed it back. "Not bad, just, whoa!"

"What does it feel like?" Toriel asked, looking up at her and resting her head back, her eyes dark with growing desire.

"It's sensitive," Undyne admitted, biting her lip for a moment. Toriel's fingers were long, ending in blunt claws, and they were very soft. "Like little bits of pleasure. Too much, and it's way too much, but just light touches... it's awesome."

"So keep my current method?"

"Yes, please," Undyne agreed, her voice a bit strained, now.

Her fingers, however, remained true, and soon she crooked them up and rubbed Toriel's soft spot with a grin. Toriel moaned softly, her eyes closing, and she moved closer, parting her legs further.

Undyne licked her lips again, shifting a little, herself. Toriel was beautiful, but she was attractive as well, and she was especially so like this, so eager and warm and comfortable.

"I wanna go down on you," Undyne blurted out, blushing when she realised she said it out loud.

Toriel looked up at her again and stared, her cheeks going red again. "Oh my, that would be wonderful," Toriel whispered, smiling.

Undyne pulled away happily and leapt down between Toriel's legs, pulling them apart and moving her face close this close, she could see that Toriel was rather nice on the eyes, and eagerly, she licked along her folds slowly. She tasted very different than Alphys, which wasn't a bad thing, and the added texture of her hair was interesting. She licked deeper, and Toriel moaned again softly and laid down on her back, her hands to her chest and her eyes closed.

This was going to be fun.

* * *

Alphys was delirious, really. She was naked, in the King's bed, with a naked king holding her close and kissing her so deeply that their tongues met, the feel smooth and glorious. His hands were on her breasts, and her legs were around his waist, close enough to feel...

"Oh my god," Alphys cried, pulling away and looking down, her eyes wide. Asgore was surprised, too, until he saw that her eyes were glued to his cock, and he coughed a little shyly.

"Whoa," she whispered. She looked up and asked, "Can-can I touch...?"

Asgore was nodding before she finished, his eyes darkening. "Please," he agreed softly.

Alphys smiled and reached down, curling her hand around the shaft of his cock slowly. Asgore took hold of her shoulders and breathed out, closing his eyes, and Alphys watched him, her heart racing.

She slowly slid her hand up, watching as the smooth skin seemed to follow her hand, and she blinked. Asgore bit his lip and inhaled, his grip on Alphys's shoulder tightening, and she took that as a good sign, moving her hand down, then back up.

Asgore rested his head atop hers, his eyes fluttering closed. Her hand was small, but firm, and she felt nervous but thrilled.

"N-nice?" she murmured.

In reply, he reached down and moved his hand between her thighs, and she jumped, then swallowed, nodding. He smiled, looking into her eyes, and he trailed his fingers past her folds and gently within, using only one finger for now, his thumb circling her clit.

"Oh god," Alphys whispered, her eyes closing for longer than a blink. His fingers were large and long - longer than Undyne's - and the one he used felt wonderful and firm within her. She shifted her hips, and he reached deeper, stroking that soft spot gently.

"Asgore!" Alphys cried, her hand stilling. "I c-can"t concentrate..."

"It's alright," he whispered, kissing her forehead, feeling hot how her skin was.

She tried, anyway, moving her hand quickly up and down the shaft of his cock, tightening when she got to the head. She'd seen and read enough to know the theory, and was proud her application was accurate, judgeing by how Asgore swayed a little with her hand's movements.

However, it was true what she said: Asgore was distracting her, and the longer he did, the harder it was for her to keep an even pace. Asgore noticed and pulled her hand away, surprising her into protesting - until he pushed her down onto the bed gently and kissed her. She clung to him, moaning deep in her throat from the feel of him against her. He was heavy, true, but it was a nice warmth, comforting and soft.

Asgore's finger started to move again, and she moaned again, squirming beneath him and shifting her hips in time to his strokes. She angled her hips - then gasped, breaking from their kiss to arch back, her eyes shutting tight.

"There," she groaned out, and he looked down at her. "There!" she repeated urgently, shifting again, her hands on his shoulders and holding tight.

"Ah," Asgore murmured, leaning down to kiss her neck, then move down to her breast. "You've one of those, too, I see."

"Yes!" Alphys replied, her voice strained. "All... women do... Some are just.... ah... easier to find than others..." She cried out, leaning forward, just as Asgore closed his lips around her nipple. "Asgore... Asgore, I'm cl-close..."

She was surprised, herself, as while it didn't take her long when that spot was touched, but Asgore's fingertip was thick and strong, and his aim was true.

"Good," Asgore murmured around her nipple. "Do come, please, Doctor."

"Oh my god," Alphys cried. She was both overcome with her body's feelings, but also the situation, too. It was so strange, so odd, yet it felt comfortable, wonderful. She was so close, now, and she loved it. "Asgore..."

She grabbed onto his arm, gasping, and she completely abandoned herself to him, her body moving against his hand hard. Asgore watched her, amazed by this transformation; he was so used to seeing her so calm and shy, and seeing her this enthralled and inflamed was... alluring. She was stunning.

"Oh god!" she suddenly cried, her body stiffening. "Oh god! Un- _Undyne!"_ She blurted it out without thinking, a hand going up and slapping over her mouth with mortification, but Asgore merely chuckled and kissed her forehead again. She was about to apologise, but when she lowered her hand, he kissed her, instead, and she relaxed - completely.

She groaned against his lips, her eyes shutting tight, and she came, clutching at him tight, Asgore slowed down his hand, and she purred, burying her face into his chest and gasping for breath, reeling. He kissed her lips again, holding her close and stroking her head as she calmed.

"Asgore," she whispered when she could, and he nodded. "I want to... keep going..."

"I do, too," he agreed.

She opened her eyes slowly and looked up at him, smiling, and he returned it - before kissing her again, harder this time.

* * *

Toriel was amazed by how good Undyne felt. The younger women knew exactly what she was doing, and she felt amazing. Her orgasm was close already, and she smiled, thrilled by that fact alone.

"Oh, Undyne," she whispered. "I'm close, dear..."

Undyne increased the pace over Toriel's clit in reply. Toriel, it appeared, was a quiet lover, and it surprised Undyne, having fully expected the opposite.

Maybe there was something she was missing. But first...

Toriel's heels were digging into the bed, and one of her hands went to Undyne's hair, the other clutched firmly to her own chest, her teeth bared and her breaths short.

With a gasp, Toriel arched back, her body flashing hot as she came, crying out softly - a sound coupled with a delighted laugh. Undyne looked up as she pulled away, surprised, and Toriel looked at her with shining eyes.

"I'd love to repay the favour, Undyne," she murmured, her hand going to Undyne's cheek.

"Hell, yeah," Undyne replied, moving up to lie down beside her. "I just wanted a royal flush, first."

Toriel laughed. "That was excellent!" she declared, clapping a couple of times and making Undyne laugh in return.

Undyne's ears suddenly twitched, and she laughed softly, shaking her head. Toriel's ears twitched, too, and she smiled.

"Sounds like Asgore's found Alphy's sweet spot," Undyne observed.

"He's very good at that," Toriel agreed. "But then, so are you."

Undyne blushed and looked away shyly, and Toriel kissed her cheek gently, before she leaned closer and touched Undyne's thigh. "May I do the same for you, as you did for me?"

Undyne's blush deepened. "Uh, if you want to... I'd really like that..."

"Lie down, dear," Toriel replied, her eyes shining brighter. Undyne did, and Toriel was between her legs, looking curious and excited. "Oh, look at that, all the way down, too!"

Undyne laughed. "Stop spazzing over my bush, Elly!"

Toriel looked up, a surprised blush upon her cheeks. She was smiling, and Undyne noticed her tail was wagging. "Elly?" she echoed. "That's very nice!"

"Sorry," Undyne mumbled. "I tend to give nicknames to people I'm... close to."

"I like it, Undyne," Toriel reassured her, and Undyne smiled, glad to hear it. "Do use it all the time. It's sweet."

"I think you're pretty damned sweet, Elly," Undyne admitted, still shy.

"Oh, stop that," Toriel replied, sounding pleased.

"It's true--,"

Toriel smirked and shut her up by kissing her right upon her folds, and she gasped and dropped back, her eye closing. Toriel's lips were warm - warmer than she expected - and felt very good.

"Fuck," Undyne whispered, a hand going up into her hair, her teeth sinking into her bottom lip.

Toriel carefully used her tongue and prised those folds apart, surprised to find the taste rather nice. She licked slowly, closing her eyes and letting the taste linger, and suddenly she found herself understanding her husband very well.

She raised an eyebrow and concentrated as the tip of her tongue moved upwards to Undyne's clit. When it touched it, Undyne gasped, arching back and digging her heels into the bed this time. "Holy fuck!" she added, tugging on her hair, her other hand going to her breast. "Your tongue... it's so _warm!!"_

"Fire magic," Toriel murmured again, before continuing, tracing Undyne's clit with her tongue slowly, bringing a moan from Undyne - a sound that made her feel very happy, indeed.

Undyne then blurted out Alphys's name in a choked whisper, before her eye flared open and she apologised, embarrassed.

Toriel, however, squeezed her knee, and didn't hesitate at all, dipping her tongue deep into Undyne's core and letting it linger. Undyne squirmed, another moan escaping her between clenched teeth, and she growled out, "Focus on my clit, hard and fast, please...?"

Toriel nodded and complied, flicking her tongue over Undyne's clit quickly and steadily, and the other woman cried out, arching back again, her hands clutching at the bed beneath her hard. "Fuck!" she shouted. "Perfect! Perfect, _don't stop!"_

Toriel certainly did not, and she found herself squirming a little, herself, getting aroused again at the sight of Undyne's pleasure - especially as she was the one giving it to her.

Undyne was definitely not a quiet lover, and felt no shame or regret in being loud whatsoever. She loved sex, loved declaring it, and a change in partner didn't change that. The closer she got, the louder she got, and honestly, for Toriel - who was used to a quieter lover - it was very arousing, something that surprised her a great deal.

Suddenly, she hoped this wouldn't be the only time they did this.

"Toriel...!" Undyne suddenly shouted, her nails digging so hard into the blankets that they ripped. "I'm...! I'm...!" She lost her ability to speak once her orgasm hit, and she arched back, both crying out and laughing, it felt that good. Toriel held her close, finding it a strain, as Undyne was very strong, and she moved very rigidly.

She then collapsed, her eye closed and her breaths hoarse, panting for breath, and she laughed, louder, this time for longer. "Holy shit," she rasped out, her hands to her chest and over her racing heart. "Holy shit, that was _so_ good... I'm jealous of Asgore, that was so fucking _hot...!_

Toriel laughed, sitting up and looking at her fondly. Undyne opened her eye and gazed at her with affection, as well, and she held her hands out, her arms open. Toriel moved away from between her legs and laid down beside her, and Undyne grabbed her into a tight hug, kissing her cheeks and laughing again.

"So it went well, did it?" Toriel then wondered, and Undyne held her closer and laughed even more. "Undyne," she then added, peering at her closely. "I've done some research, and I'd love to know what tribbing is."

Undyne stared at her, her grin growing larger the longer she stared. "Oh, fuck, yes please," she agreed, reaching for Toriel and kissing her lips hard, pulling her close.

Toriel's heart raced with excitement as she kissed back, wrapping her arms around Undyne's neck and pulling her down atop her. She figured it would be best if Undyne was on top, as she at least knew what she was doing. Undyne clearly agreed, already moving to adjust them both with practised ease.

When they were close enough, Undyne reached between them and adjusted first her own, then Toriel's, clits carefully, before she lowered herself down and rubbed against Toriel closely.

"Oh my!" Toriel cried, her eyes flaring with surprise. She looked up at Undyne, who grinned at her with a flashing eye. "That's _very_ nice!"

"Hold that thought," Undyne replied slyly, leaning down and grabbing hold of one of Toriel's nipples with her lips. Then, she started to move, and Toriel's eyes widened even more, smiling in delight. Undyne laughed, Toriel's reaction tickling her.

Undyne kept the pace steady at first, but then decided to go faster, eager to see if she could make Toriel get loud. Toriel cried out and closed her eyes, holding onto Undyne tighter, and Undyne switched nipples, her eye closing.

Toriel was far bigger than Alphys, but it different - just different. She was soft and warm, and a damn good kisser. She wasn't worse or better than Alphys - just new and different.

"Undyne," Toriel murmured, and she raised her head. "Can you move your hips to the right?"

Undyne did, then resumed, and Toriel clung to her, moaning softly. She kissed Undyne's neck, making her shiver, and she increased her pace without thinking.

Toriel, however, was thrilled. This was nothing like she was used to, or expected, but she liked it a great deal. All attention was on her clit, and the pressure and rhythm Undyne applied to her was perfect. It was a version of sex she found she could truly get addicted to, the pleasure blooming from deep within, and she loved each moment.

"Undyne, thank you," she murmured, gasping a little.

"Huh? Why?" Undyne answered, her voice catching a little.

"I'd never know this if it weren't for you. It's truly a gift."

Undyne blinked. Toriel was looking up at her with glazed but warm eyes, sincere in all of her words. "Thank you, too," she stammered, unsure of what else to say. So to cover it up, she kissed Toriel's lips, hard, and Toriel clung to her, kissing back almost desperately.

"Undyne," Toriel then whispered, crying out between sentences. "I'm close."

"Good," Undyne replied, leaning down and kissing Toriel's soft neck, bringing another moan from her. Undyne then increased the pace, gasping a little, herself, and Toriel cried out, several times this time, holding onto Undyne tight.

"Perfect," Toriel breathed out.

Undyne grinned, then bit down lightly on her neck. Toriel arched back and keened out, surprising them both, before Toriel stopped caring altogether, crying out without care, feeling her second orgasm creep up into her before crashing hard, sending her reeling and clinging to Undyne tight.

Undyne slowed down to draw it out, and Toriel moaned gratefully, kissing Undyne's shoulder and panting. Undyne stopped, then pulled away, lying down next to Toriel and smiling down at her. Toriel turned and clung onto her again, shuddering, and Undyne kissed her forehead, holding her close to calm her down.

Then, they both laughed softly, thrilled by what just happened between them.

* * *

"Alphys," Asgore murmured, "are you alright?"

"Y-yes," she agreed, though her voice was a little hoarse.

"Would you like to--?"

 _"Yes!"_ she cried, reaching for him and pulling him down to kiss him again, but he stopped her.

"Alphys, this is your first time with a man?" he asked, and she blushed, nodding. Gently, he pulled away, and she looked confused. She was about to ask, but he simply laid down beside her on his back. "Come on top of me."

Alphys hesitated, sitting up and holding her hands up in front of her, her eyes then moving down - to see that Asgore's cock was still erect and hard. She moved her hand to take hold of it, but again he stopped her, pulling on her arm gently. She looked up, then finally understood, and placed her hand on his chest, instead. She moved closer, then straddled him, hovering just a little over his cock, unsure of what to do.

"I want you to go as slow as you need, and not worry about me," he told her softly.

"R-right," she murmured. "Because it could hurt. I forgot. O-okay." She fidgeted for a moment, then took hold of his cock at the base and moved down, angling so that they lined up. She then moved her hand to herself, making sure she was slick enough, before she swallowed hard, hesitating again.

Her eyes met Asgore's, and he smiled at her, touching her cheek gently. She closed her eyes and relaxed, feeling better, and she moved down close, so that the head of his cock met between her folds. She opened her eyes when she did that, and saw his eyes close, his other hand going to her hip. She blinked, so far feeling fine, and she shifted down lower, feeling a little thrill when he inhaled sharply, his other hand going to her other hip.

Feeling a little daring, now, Alphys shifted her hips and moved down completely.

And she stopped, her eyes flaring and a small cry escaping her. It _did_ hurt, but not in the way she always read it would in books and fics. It stung for a moment, as though Asgore pushed against something, before she felt a sharper sting and something give. The moment that happened, he was fully inside of her without anything holding him back, and he hit deep - and suddenly there was no pain whatsoever.

"Oh my god," she whispered, her hands going to his chest, and he looked up at her worriedly, despite his gritted teeth. But then she added, "That feels so good," and he immediately relaxed, smiling and holding her hips tighter.

"Start moving however you like," Asgore then advised, and she opened her eyes, still catching her breath, before she nodded.

She shifted her hips, just a little, and she felt another spark of pleasure hit her. But Asgore cried out, surprising her, and she stopped. "Was that bad?"

"No," Asgore said immediately. "That was wonderful."

Alphys smiled faintly, then leaned down and kissed him. He returned it with fervour, his arms wrapping around her, and he suddenly moved his hips up, making her squeak and her eyes widen, surprised by how good that felt. Asgore smiled, deepening their kiss and doing it again, and Alphys pushed down to meet him, her eyes closing and her claws digging into his chest a little, crying out again.

They moved slowly to start, easing Alphys into it, as she was still a little tender - though again, not even close to what she'd always read - but that didn't stop how good it felt, for both of them.

Alphys was a larger monster, true, but she was smaller than Asgore, and thus actually felt a little snug around his cock. It wasn't uncomfortable, though, as she was very slick, but it did increase his pleasure, which surprised him. Alphys, in turn, was overwhelmed, but in a good way. He wasn't overtly long, but he was on the thick side, and feeling him inside her was a feeling like no other she'd ever known.

"Asgore," she cried, pulling away to bury her face into his shoulder. She wrapped her tail around his thigh, and he smiled, his eyes closed tight and his breaths catching.

"Yes?" he whispered, kissing her cheek.

"This is... this is so... g-good," she blurted out, knowing she was babbling but unable to help herself. "I... I want to... Can you...? Oh god..."

Asgore chuckled softly, kissing her cheek again. "Take your time."

Alphys nodded, swallowing hard, but not stopping the pace. Neither of them hesitated; they were already synced, finding it easy to adjust. It wasn't so strange, as they'd been friends for years, now, but it was a nice surprise, all the same.

"Please..." Alphys whispered, finding it hard to talk, now. "Please come on top, now?"

Asgore nodded, wanting the same, and glad that she mentioned it, first. She moved to climb off, but he took hold of her and rolled her over. He propped himself up on his hands, and she grabbed hold of him and ground her hips against his, and he grunted, lowering his head in surprise.

"M-more," she pleaded into his ear, her voice rasping around the edges. She wrapped her arms around his neck and buried her hands in his hair, her face going back to his chest.

Asgore lowered down onto his elbows and held her close, then started to move, slow strokes at first, watching her closely to make sure he wasn't hurting her - and finding that he was doing the exact opposite.

"Faster," Alphys begged, proving him right. "And just... j-just higher... a b-bit..."

Asgore shifted, taking hold of her hips again to raise her up closer against him, before he lowered down again and resumed thrusting into her, this time harder and faster, a soft moan escaping him as he did.

"Y-yes--!" Alphys cried, throwing her head back and meeting his thrusts urgently, her whole body flushing hot. He hit right at her soft spot with each thrust, and her body was already flooding with pleasure, already sensitive from her previous orgasm.

Asgore watched her, his eyes half-open, already close, himself. She gripped him tight, her body moving so intensely against his, that he couldn't hold back no matter how hard he tried.

"Und--s-sorry-- As-Asgore...!" Alphys cried out, her claws digging into his chest and her tail grabbing hold of his thigh again. "I'm--!" She keened out, her eyes squeezed closed tight, and she didn't stop, especially when she finally came - and came hard.

For Asgore, her sounds, the feel of her flashing hot and gripping hard on his cock, was simply too much to hold back from any longer, and with a sharp cry of his own, he followed her. Alphys gasped, feeling it deep within her, and he cried out again, louder, the power behind his orgasm taking his breath away.

Alphys collapsed beneath him, gasping and letting go of him, and he opened his eyes, surprised. "Alphys?" he murmured, touching her cheek gently. She stirred, but didn't open her eyes or speak, and he moved off of her quickly, remaining close but staying off of her. "Alphys?" he repeated, touching her cheek again and tapping it lightly.

"Undyne?" he then called, feeling panicked. "Undyne?!"

* * *

Undyne opened her eye and sighed, sitting up slowly and stretching. Toriel blinked up at her tiredly, confused, and Undyne blushed.

They heard Asgore call for Undyne again, louder.

"I forgot to warn him," Undyne explained, getting to her feet. "Alphys passes out if fucked real good."

Toriel laughed, following her, and Undyne went over and opened the door, padding across the hall towards the other bedroom - forgetting she was naked at first but not really caring once she realised - and knocked on the door, before opening it.

Asgore was still lying down beside Alphys, still trying to wake her and looking panicked, and when Undyne walked over, he sat up and started to protest.

"Shut up," Undyne replied happily, lying down on Alphys's other side and curling up next to her. Alphys again stirred, and Undyne touched her cheek, pulling her close and kissing her lips softly.

Alphys moaned faintly, her eyes flickering open and meeting Undyne's, their colour dark and glazed over with bliss. Undyne smiled at her, and she smiled back. (Beside her, Asgore relaxed, closing his eyes and curling up next to Alphys's other side.)

"You okay, love?" Undyne wondered.

"I was right..." Alphys whispered, touching Undyne's hand. "He really _is_ dreamy..."

Undyne laughed and kissed her again, and Alphys giggled tiredly.

Toriel went to Asgore, kissed him, then went to Undyne's other side, lying down next to her and spooning her with a kiss to her shoulder. Undyne smiled at her and shifted, so they were all comfortable.

Soon, after a comfortable, amazed silence, all four dozed off, curled up together like cats in a sunbeam, and equally content.

* * *

"No, Elly, you gotta _punch 'em,_ right in their stupid faces."

"Like this?"

"Ugh, you're worse than your damned kid, and they're human! Stop petting the enemy!"

Asgore's eyes met Alphys, and they both raised an eyebrow, amused. Toriel and Undyne were both in the kitchen, having decided to make supper for the four of them - with mixed results. The two of them had opted for tea, having been threatened with spears and fire if they interfered.

"So," Asgore said softly. "How do you feel? Are you alright?"

"Oh!" Alphys lowered her cup and beamed at him. "Yes! I feel wonderful!"

Asgore beamed in return. "That's good! Golly, you frightened me, I'll be honest."

Alphys blushed. "I-I'm sorry! But it was so good, really!"

Asgore chuckled. "I agree." His smile softened. "Alphys, I quite enjoyed my time with you. You were quite a handful, in a very enjoyable way."

"Me too, with you, I mean," Alphys agreed shyly. "Though I wish I had been able to go down on you."

Asgore blushed, sipping his tea, as he suddenly had that same thought, and found it rather distracting.

Alphys eyed him. "Did you... feel jealous at all?"

"No," he replied easily. "I love all three of you, and if we bring each other pleasure, with no hard feelings between us, what is there to be jealous of?"

"I agree," she admitted. "I was afraid I would be too jealous to enjoy this, but... that wasn't how it felt at all."

"It was like being with a friend," he said, and she nodded, smiling brightly. That was it exactly.

"So, Elly," Undyne said, trying to sound casual. "D'you think you two would wanna do this again?"

"Yes," both Toriel and Asgore suddenly said as one, surprising the four into a small, shared laugh.

"I mean," Toriel added, touching the tomatoes fondly. "If the two of you would like to."

"Yes please!" Alphys blurted out.

Undyne nodded. "Yeah," she agreed. "That was... really fucking fun."

"Pun intended?" Asgore teased.

"Hell, yeah!" Undyne agreed with a grin, before she suddenly snarled. "Punch them, dammit! Like this!" And she flung her fist out and smashed it into a green pepper, smushing it against the wall.

Toriel's eyes suddenly lit up. "Oh, like this?" she asked, before she swung her arm and, with a burst of fire, exploded her tomato against the counter.

Undyne stared at her, bright red. "Oh, fuck, yes," she agreed, leaning down and kissing Toriel and pulling her close. Toriel returned it, suddenly intrigued by this.

Alphys snorted into her tea, and Asgore chuckled. They exchanged a glance, and beneath the table, their toes touched.

It ended up being a lasting, decades-long agreement, one none of them ever regretted.


End file.
